In this study，a wafer-level packaging（WLP）process for surface acoustic wave（SAW）filters，based on silicon cap bonding technology，is developed to meet the stringent requirements for hermeticity，mechanical strength，and thermal performance in high-frequency communication systems. A packaging structure with superior hermeticity，thermal dissipation，and reliability is formed by optimizing the deep silicon etching process of through-silicon via（TSV）holes and the LT layer etching process，followed by depositing an SiO2 passivation layer using the low-temperature plasma enhanced chemical vapor deposition method（PECVD）. Reliability tests demonstrate that the silicon-cap-bonded WLP exhibits a frequency drift of only 2M to 2.5M（B40 band）after unbiased highly accelerated stress testing（uHAST），significantly outperforming traditional polyimide-based WLP（5M to 6M）. This process provides robust technical support for high-performance wafer-level packaging of SAW filters.