Research Scientist Intern (TikTok Recommendation-Large Recommender Models) - 2026 Start (PhD)

You'll be joining the TikTok Recommendation team focusing on advancing large-scale recommender systems that power TikTok’s personalized content discovery and user experiences. By developing cutting-edge models, we aim to optimize recommendation accuracy, user engagement, and scalability across billions of users. We’re looking for Machine Learning Scientists passionate about building high-performance, scalable recommendation systems. You’ll leverage advanced deep learning techniques and large-scale systems engineering, collaborating with cross-functional teams to solve complex challenges in personalization and recommendation at scale.

We are looking for talented individuals to join us for an internship in 2026. PhD Internships at TikTok aim to provide students with the opportunity to actively contribute to our products and research, and to the organization's future plans and emerging technologies.

PhD internships at TikTok provide students with the opportunity to actively contribute to our products and research, and to the organization's future plans and emerging technologies. Our dynamic internship experience blends hands-on learning, enriching community-building and development events, and collaboration with industry experts.
Applications will be reviewed on a rolling basis - we encourage you to apply early. Please state your availability clearly in your resume (Start date, End date).

Responsibilities
- Research and develop large-scale recommender systems for personalized, engaging user experiences, focusing on scalability, accuracy, and performance.
- Apply advanced machine learning and deep learning techniques to optimize recommendation algorithms for TikTok’s diverse user base.
- Manage the end-to-end lifecycle of recommender models, from training and fine-tuning to deployment, monitoring, and continuous improvement.
- Analyze complex data to uncover user preferences, behaviors, and trends, driving personalization and enhancing TikTok’s recommendation capabilities.
- Collaborate with cross-functional teams (infrastructure, product, research, etc.) to design and implement innovative solutions that improve the relevance and diversity of TikTok recommendations.