In　small-scale　geotechnical　experiments,　using　a　tactile　pressure　sensor　(TPS)　to　measure　soil　pressure　distribution　on　a　curved　surface　can　effectively　reduce　errors　of　mismatch　caused　by　size,　stiffness,　and　incomplete　fitting　with　the　measured　object.　TPS　has　more　benefits　than　soil　pressure　cells　in　measuring　curve　surface　pressure,　but　some　issues　remain　unclear,　such　as　the　effect　of　negative-piezoresistivity　and　particle　size　on　the　measurement.　In　this　article,　the　author　first　puts　forward　a　method　to　effectively　reduce　the　errors　of　TPS　in　the　low-pressure　measurement　zone.　Then,　through　a　load　test　in　six　types　of　narrow-graded　sand,　the　ratio　of　the　maximum　particle　size　to　the　size　of　the　sensor　unit　is　obtained,　and　the　effect　of　negative　piezoresistivity　on　the　measurement　is　evaluated.　Finally,　a　small　laboratory　test　proves　that　TPS　can　comprehensively　and　meticulously　reflect　the　pressure　on　the　pile.　After　careful　calibration　and　considering　the　effect　of　deflection　and　particle　size,　it　is　shown　that　the　measurement　errors　can　be　kept　within　an　acceptable　range.