The invention provides a solar steam cooker having a solar tube enclosing an inner space and having a close end and an open end, a cover closing the open end, an inner container in the inner space of the solar tube and being rotatable with respect to the solar tube, a sleeve covering on the close end of the solar tube and having an axle, and, a strut supporting the axle of the sleeve. The solar tube is of glass and has a translucent outer layer, a blackbody inner layer and a vacuum space between the outer and the inner layer. The cover has a circular groove covering on the open end of the solar tube. The inner container has a top opening.