Abstract: Disclosed is a new collapsible boat trailer for low speed, short distance vehicle-towed transport, launching, and retrieval of lightweight boats which is quickly disassemblable without tools into small lightweight components for stowage. The collapsible boat trailer comprises a rigid frame which includes a tubular cross member with a forward extending towing bar coupling structure fixedly connected centrally intermediate the ends thereof. A wheel assembly extends downwardly from both ends of the cross member whereby the boat trailer may roll across the ground. The upper ends of the wheel assemblies are pivotally connected to the cross member such that they may be pivoted inwardly upwardly to lie adjacent the cross member for inoperable stowage. An elongated two-piece towing bar extends from the front of the towing bar coupling structure. The towing bar is separable from the frame, as are the two pieces of the towing bar separable from each other for inoperable stowage.