The　design　of　a　contact　PVDF　acoustic　sensor　is　described　in　this　paper,　including　the　operating　principle　and　the　structure　of　the　sensor,　and　the　influence　of　backing　material,　acoustic　matching　layer　and　pre-amplifier　on　the　sensitivity,　resolution　and　signal　to　noise　ratio　(SNR)　of　the　sensor.　The　sensor　has　been　calibrated　using　a　precision　impedance　analyzer,　by　which　the　parameters　of　the　acoustic　sensor　have　been　obtained.　Test　result　shows　that　the　design　method　is　acceptable.