A releasable connector for electric circuits is composed of a male connector housing and a female connector housing adapted to be fittable in each other. One of the connector housings is provided with a resilient short-circuit member while the other is provided with an insulator member. When the two parts are released from each other, the short-circuit member is resiliently urged against the upper surfaces of the terminals in the one connector housing so as to make a short circuit between the terminals. When the two housings are coupled together, the insulator member in the other connector housing wedges in between the short-circuit member and the terminals in the one connector housing so as to break the short circuit made therebetween. With this construction, it is ensured that any current being induced by and under the influence of external magnetic fields or electric fields or static electricity within the system to which the invention is applied is prevented from flowing through the associated circuit elements thus avoiding malfunctions of the elements.