A collapsing device for a golf cart includes an upper rod provided with a lengthening unit, a lower unit connected to a lower rend of the upper rod, and a collapsing unit provided between the upper end of the lower rod and the upper rod. Further, a folding unit is provided on the upper portion of the upper rod, permitting the golf cart collapsible to a size as small as possible in cooperation of the lengthening unit and the collapsing unit to lower cost for package and transporting.