Automated translation of legacy C code into Rust aims to ensure memory safety while reducing the burden of manual migration. Early approaches in code translation rely on static rule-based methods, but they suffer from limited coverage due to dependence on predefined rule patterns. Recent works regard the task as a sequence-to-sequence problem by leveraging large language models (LLMs). Although these LLM- based methods are capable of reducing unsafe code blocks, the translated code often exhibits issues in following Rust rules and maintaining semantic consistency. On one hand, existing methods adopt a direct prompting strategy to translate the C code, which struggles to accommodate the syntactic rules between C and Rust. On the other hand, this strategy makes it difficult for LLMs to accurately capture the semantics of complex code. To address these challenges,we propose IRENE, an LLM-based framework that Integrates RulEs aNd sEmantics to enhance translation. IRENE consists of three modules: 1) a rule-augmented retrieval module that selects relevant translation examples based on rules generated from a static analyzer developed by us, thereby improving the handling of Rust rules; 2) a structured summarization module that produces a structured summary for guiding LLMs to enhance the semantic understanding of C code; 3) an error-driven translation module that leverages compiler diagnostics to iteratively refine translations. We evaluate IRENE on two datasets (xCodeEval—a public dataset, HW-Bench—an industrial dataset provided by Huawei) and eight LLMs, focusing on translation accuracy and safety. In the xCodeEval, IRENE consistently outperforms the strongest baseline method in all LLMs, achieving average improvements of 8.06% and 12.74% in the computational accuracy (CA) and compilation success rate (CSR), respectively. It also enhances the safety of translated code, reducing the Unsafe Rate (UR) to 1.70% on average. In the HW-Bench, when compared to the strongest baseline, IRENE improves CSR and reduces UR by an average of 0.33% and 26%, respectively.