Lead iodide (PbI2) microcrystals based photodetector were developed by a simple printing method. Carbon composite paste was fabricated by homogeneous mixing of PbI2 microcrystals, commercial graphite powder, and activated carbon. Composite carbon paste was printed on top of thermally deposited Al electrodes on the glass substrates to fabricate the photodetector. Controlled variation of PbI2 loading established that 10% PbI2 in carbon composite is the best candidate for the highest On/Off ratio. The photo generated current was manifested by the defect present in the graphite and the PbI2 microcrystals interfaces. The effect enables us to develop cost effective printing based photodetector which can work in very low voltage region for low‐power printed electronics.