Abstract: A bicycle operated watercraft assembly is disclosed. A bicycle is mounted on a main framework including front and rear outrigger arms to which are secured a pair of laterally spaced floats. The front wheel of the bicycle is disposed in a rotatable channel to which is secured a steerable paddle for controlling the course direction of the watercraft. Propulsion paddles are rotatably secured at the rear of the main framework. The paddles are driven from the bicycle through the drive chain which is operatively connected with a shiftable gear train mounted on the drive shaft for the paddles. The bicycle is secured in place by front and rear struts which are adjustable in length to support different sized bicycles. Rear brackets hold the bicycle against rearward movement during operation.