Senior UX Researcher- Mercari Marketplace (Commerce New Service)

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Senior UX Researcher- Mercari Marketplace (Commerce New Service)

• Employment Status: Full-time
• Work Hours: Full Flextime (no core time)
• Office: Roppongi

For more details, see the Overview of Our Positions section on our Careers site.

About Mercari

Circulate all forms of value to unleash the potential in all people

"What can I do to help society thrive with the finite resources we have?" The Mercari marketplace app was born in 2013 out of this thought by our founder Shintaro Yamada as he traveled the world. We believe that by circulating all forms of value, not just physical things and money, we can create opportunities for anyone to realize their dreams and contribute to society and the people around them. Mercari aims to use technology to connect people all over the world and create a world where anyone can unleash their potential. For more information about Mercari Group’s mission, see Mercari’s Culture Doc

Organization/Team Mission

The New Business Design Team leads end-to-end user experience design for emerging product initiatives at Mercari, shaping intuitive, trustworthy, and high-quality experiences for domestic and international users. We partner closely with Product, Engineering, Research, and Business Development to explore new problem spaces and raise the bar for craft, consistency, and innovation.

See here for more information about our mission and values.

Why this role matters

We are seeking a User Researcher to join the New-Business research team.

The New Business organization at Mercari is focused on identifying and scaling transformative opportunities that expand Mercari's market reach and unlock new revenue streams. We pursue zero-to-one initiatives and strategic bets across emerging commerce models, user segments, and geographic markets—from expansion into new verticals to testing innovative transaction types. Our team operates at the intersection of exploration and execution, moving quickly to validate concepts while maintaining rigor in decision-making.

We are seeking an experienced User Researcher to join the New Business UX research function at Mercari. This role requires full-stack research capability—the ability to move fluidly between lightweight tactical research (rapid testing, feedback collection, quick iterations) and deeper strategic research (market exploration, business model validation, strategic recommendations), while also leading research initiatives independently and partnering cross-functionally with product, design, and business teams.

You will own research strategy for assigned new business initiatives, ranging from early-stage market exploration to validation of emerging concepts. You'll design and execute a mix of qualitative and quantitative research methods—from quick concept tests and user feedback loops to in-depth ethnographic fieldwork and large-scale validation studies—and synthesize findings into clear, actionable recommendations that directly influence business direction and product decisions. You're equally comfortable running a one-week validation sprint as you are designing and leading a multi-month strategic research initiative.

As the research voice in an exploratory, fast-moving environment, you'll need to balance rigor with speed: designing research that generates confidence in decision-making while moving quickly enough to support iterative business hypothesis testing. You'll also play a key role in building research operations and practices for the new business org, helping establish scalable processes, repositories, and frameworks that mature as we grow and that can be shared across Mercari.

This role is ideal for a researcher who thrives working with ambiguity, who has demonstrated success leading research independently (not just executing), who brings international and cross-cultural perspective, and who is excited by the challenge of validating entirely new business models and market opportunities.

Work Responsibilities

Strategic Research Leadership

• Lead end-to-end research initiatives for new business concepts, including framing research questions, designing methodology, managing timelines, and communicating findings to senior leadership and stakeholders.
• Conduct international and cross-cultural user research, including planning and executing fieldwork in key markets (e.g., US, Asia-Pacific regions) to understand local user behaviors, market dynamics, and competitive landscapes.
• Partner with product, business development, and design leads to translate business hypotheses into rigorous research frameworks that test viability and reduce risk.
• Make methodological choices that balance research rigor with business velocity—knowing when to run quick validation tests vs. deeper exploratory studies.
• Synthesize research findings into strategic recommendations and business insights that inform go/no-go decisions, product strategy, and market entry decisions.

Research Operations & Infrastructure

• Establish and evolve research ops best practices for the new business organization, including participant recruitment strategies, repository management, and insight communication frameworks.
• Build and maintain research repositories, market databases, and competitive intelligence systems that enable ongoing learning across new business initiatives.
• Support research at scale by leveraging AI tools thoughtfully across the research workflow—from study planning and participant recruitment to analysis, synthesis, insight visualization, and reporting.
• Help establish shared research artifacts (playbooks, templates, frameworks) that enable rapid research execution and knowledge sharing across the new business team.

Cross-functional Collaboration & Stakeholder Management

• Partner with PMs, designers, marketing and business development stakeholders to identify research needs early and embed research into decision-making cycles.
• Communicate research findings effectively to diverse audiences—executives, product teams, and design partners—adapting communication style and rigor to stakeholder needs.
• Build trust and credibility with stakeholders through transparent research practices, clear methodology communication, and a track record of actionable insights.
• Mentor and support junior researchers or contractors as the team grows.

Continuous Learning & Innovation

• Stay current with research trends, methodologies, and tools—particularly in international research, business model validation, and emerging commerce spaces.
• Explore and advocate for thoughtful applications of AI in the research function, helping Mercari develop a more efficient, innovative research practice.
• Contribute to the broader UX research community at Mercari, sharing frameworks and learnings across teams.

Unique Challenges (Looking for someone who is…)

• Full-stack and versatile: Comfortable moving between modes—able to run quick, lightweight validation tests one week and design a rigorous multi-month strategic research initiative the next. You don't mind getting hands-on with execution, but you're also capable of stepping back to think strategically about research direction.
• Strategically minded: Able to frame research questions that directly address business risk and opportunity. You understand how research fits into augments business decision-making, not just design iteration.
• Intellectually rigorous: Comfortable defending methodology choices, challenging assumptions (yours and others'), and insisting on evidence-based thinking—even under time pressure.
• Operationally savvy: Excited to build research infrastructure and processes—not just execute individual studies, but help create scalability and organizational capability as the team grows.

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