Organophosphorous pesticide (OP), one of the most commonly used pesticides, could have serious adverse effects on human health and the environment. As the maximum residue limit (MRL) of OPs in food and water is low, it is in great demand to develop integrated, portable, userfriendly devices for the rapid and sensitive detection of OP residue. This work aims to present a homemade handhold device and screen printing electrode (SPE) chip for rapid, sensitive, and onestep detection of OPs. A handhold device was designed and fabricated to connect with smartphone to readout the electrochemical signals. Taking advantage of a threeelectrode sensor chip and the inhibiting reaction of acetylcholine esterase (AchE), Trichlorphon can be detected in a considerable low detection limit of 1 ng/mL. By using the asfabricated device and chip, the detection time was only 5 min and each test costs less than ￥1. The platform will allow pointofcare testing (POCT) of OPs and other targets, which shows promise for healthy and environmental monitoring.