Acquiring customer requirements (CRs) is important for enterprises to compete in marketplace since inexhaustible innovation chances could be discovered from CRs. However, it is insufficient to generate ideas for innovation solely depending on the market-pull CRs acquisition method or technology-driven CRs acquisition method. From the time dimension, these two traditional methods put different emphasis on CRs: the market-pull method focusing on digging CRs for design improvement from existing products while the technology-driven method pays more attention on CRs that future products need to satisfy sustainability in the market. This paper proposes a systematic approach for CRs acquisition on the basis that CRs at different time period have different impacts on innovation. The two traditional acquisition methods can be integrated based on time iteration. Firstly, CRs are divided into past customer requirements (PCRs), current customer requirements (CCRs) and future customer requirements (FCRs) in time dimension. Secondly, we believe that PCRs and their potential evolution information can be acquired by analysis of patents, CCRs can be identified by making use of tools in the market-pull CRs acquisition method, and FCRs can be predicted through evolutionary knowledge in TRIZ. Finally, a case study is provided to validate the feasibility of the approach.