Abstract: The moisture-detecting water source shutoff device may allow a user to detect the intrusion of water into an interior space where it is not desired, contain the water intrusion, automatically shut off the supply of water to the affected area, and emit an audio or visual alarm to a user of the system. The moisture-detecting water source shutoff device may specifically comprise a drip tray that may contain the water intrusion and prevent damage to the surrounding area, a plurality of sensors within the drip tray to detect the water intrusion, a plurality of shutoff valves that may be closed by the sensors detecting an intrusion, and the ability of a user to manually start, stop, and reset the valves. The device may further comprise a mechanism that allows the user to drain the drip tray without removing the appliance, and a wireless connectivity to the user's smart phone and home security system.