A water-activated bobber release device has a housing, a bobber assembly, a spool and a line, a bobbin assembly with a dissolvable tablet, a screw extending through a central hole in the bobber assembly and a center hole in the dissolvable tablet of the bobbin assembly, and a cap with an aperture and a valve between the aperture and the bobbin assembly. The screw engages the bobbin assembly and a threaded fastener to compress a spring. When the device is submerged in a body of water at a certain depth, the pressure opens the valve to allow water to enter. The water dissolves the tablet which collapses the bobbin assembly, and the spring forces the bobber away from the housing. Once released from the housing, the bobber is free to float to the surface of the water allowing for the retrieval of the submerged item attached to the housing.