Harvesting ambient mechanical energy from the environment has gained immense interest due to its application in energy harvesting and active sensing. Herein, an ABO3 class ferroelectric semiconducting material BaTiO3 nanoparticles are used, and Antimony (Sb) is used as a dopant, which can be able to enhance the piezoelectric coefficient of BaTiO3 to a higher level, leading to increased energy‐harvesting performances. The fabricated antimony‐doped barium titanate [Sb‐doped BaTiO3 designated as (BST)] is then blended with polydimethylsiloxane (PDMS) to prepare a composite film. Electrodes are then attached with the composite film on either side to fabricate the flexible composite piezoelectric nanogenerator (FCF‐PENG) device. The fabricated FCF‐PENG device generates a maximum electrical output of peak‐to‐peak 28 V and 1.5 μA, respectively. The device also shows a good power density of 1.6 mW m−2 at the load resistance of 80 MΩ. At last, a real‐time impact sensor was fabricated to employ the device as the wearable impact sensor. The fabricated impact sensor detects the impact from high to low upon the human collision impact tested within the laboratory and the impact values are recorded and monitored with indicator using ESP32 microcontroller and ThingSpeak cloud. The above analysis and the real‐time experiments proved that the fabricated impact sensor paves the way toward sports healthcare and rehabilitation with Internet of Things (IoT) devices soon.