Abstract: The inflatable solar energy collector includes an inflatable cell supported in a frame. The frame may be adjustable to maximize the angle of exposure for the inflatable cell. Each inflatable cell includes an outer, transparent bladder and an inner, blackened bladder. A central partition runs through both inner and outer bladders to be mounted to the frame. The central partition maintains the inflatable cell taut on the frame. Both bladders include at least one vent hole, and at least the inner bladder has openings for air inlet and air outlet to define and control flow of medium therein. When inflated, the medium inside the inner bladder heats up from solar energy, and the heated medium is passed on for use. The inflated outer bladder provides insulation for the inner bladder. A plurality of inflatable solar energy collectors may be arranged in an array.