An optical sensor module and a sensor chip thereof are provided. The optical sensor module includes a substrate, a sensor chip and a passive chip. The sensor chip is disposed on the substrate, and the sensor chip includes a chip body having an active region located at a top side thereof and a recess portion depressed from a top surface of the chip body. The passive chip is accommodated in the recess portion, and a depth of the recess portion is greater than a thickness of the passive chip.