Provided are a module assembly, a connector, and an electronic device, the module assembly including a first module that includes a pin configured to selectively protrude from a side thereof, a pin installation portion in which the pin is installed to be movable, and a first magnet configured to attract the pin into the pin installation portion, a second module to be coupled to the first module, the second module including a pin receiver configured to receive the pin when the pin protrudes from the first module, and a second magnet configured to attract the pin into the pin receiver, wherein the second magnet is configured to apply, to the pin, a greater magnitude of magnetic force than the first magnet in a case in which a distance between the first module and the second module is less than a preset distance.