ChatCell is an application framework that makes single-cell analysis easier and more intuitive by leveraging natural language processing. It first transforms single-cell RNA sequencing data into a format easily understandable by large language models (LLMs). It then uses templates to integrate this single-cell language with task descriptions and target results, creating comprehensive single-cell instructions. To enhance the LLM's expertise in the single-cell domain, it undergoes vocabulary adaptation using a specialized single-cell vocabulary library to expand the model's knowledge base. Subsequently, it utilizes unified sequence generation to empower the model to proficiently execute various single-cell tasks.