Reliable　monitoring　the　movement　amplitude　and　dynamics　during　sports　exercise　is　significant　for　improving　training　results　and　preventing　training　wound.　Here,　we　present　a　printed　perovskite-based　photodetector　for　real-time　and　quantitative　monitoring　of　sports　motion.　The　ordered　nucleation　and　growth　of　perovskite　crystals　are　regulated　by　the　4-acetamidothiophenol　(AMTP)　at　the　interface,　which　promotes　the　size　of　perovskite　crystals　into　the　micrometer.　Benefiting　from　the　uniformity　of　the　AMTP-regulated　MAPbI(3),　the　as-prepared　photodetector　gives　great　photocurrent　response　under　indoor　light　or　outdoor　light.　During　the　exercise,　real-time　monitoring　sports　motion　is　achieved　through　detecting　the　illumination　changing　of　photodetectors　attaching　on　the　wrist　and　ankles.　Moreover,　twelve　kinds　of　common　sports　can　be　quantitatively　analyzed　with　the　detection　of　illumination　changing　on　the　photodetector.　Such　photodetector　provides　an　efficient　measurement　method　of　wearable　electronics　for　sports　monitoring.