A　saw-toothed　microstructure-based　flexible　pressure　sensor　was　designed　as　the　signal　readout　for　point-of-care　(POC)　immunoassay　of　carcinoembryonic　antigen　(CEA).　In　this　portable　POC　bioassay,　the　sandwich-type　immunoreaction　was　first　carried　out　to　capture　the　target　on　a　microplate,　which　simultaneously　introduced　the　platinum　nanoparticles　(PtNPs).　Upon　adding　hydrogen　peroxide　(H2O2),　the　pressure　as　the　bridge　between　the　molecular　recognition　event　and　detectable　signal　was　increasing　rapidly,　resulting　from　the　decomposition　of　H2O2　accelerated　by　PtNPs.　Meanwhile,　a　flexible　pressure　sensor　was　fabricated　with　high　sensitivity;　the　ability　of　the　pressure　response　was　dramatically　improved　by　adopting　the　saw-toothed　microstructure.　By　coupling　with　the　pressure　sensor,　the　pressure　change　could　be　monitored　in　real　time　to　achieve　the　portable　detection　of　CEA.　Under　the　optimum　conditions,　the　proposed　pressure-based　bioassay　presented　good　sensing　performance　within　0.1-40　ng/mL　at　a　detection　limit　of　87　pg/mL.　The　reproducibility,　precision,　and　accuracy　provided　by　the　method　were　also　studied　and　satisfied.　©　2019　American　Chemical　Society.