A collapsible computer mouse includes a main cover, a collapsible portion, and a hinge assembly hinging the main cover and the collapsible portion. The hinge assembly includes a first bracket, a second bracket, a restricting member, at least one resilient member, a fastener, a third bracket, and a connecting member. The first bracket, the second bracket, the restricting member, the resilient member, and the fastener are sleeved on the shaft. A protrusion is formed on of the first bracket or the restricting member, and a sliding slot is defined in the other. Elastic force created by the resilient member engages the protrusion in the sliding slot, such that the hinge assembly is self-locking.