Qwen2.5-Coder-1.5B is a large language model in the Qwen2.5-Coder series, focusing on code generation, reasoning, and debugging. Built upon the robust Qwen2.5 architecture, this model has significantly expanded the training tokens to 5.5 trillion, incorporating source code, textual code bases, synthetic data, and more, making it a leader among open-source code LLMs, rivaling GPT-4o's coding capabilities. Moreover, Qwen2.5-Coder-1.5B has enhanced its mathematical and general capabilities, providing a more comprehensive foundation for practical applications such as code agents.