Many experimental and numerical studies have been done on different configurations of solar stills to optimize the design by examining the effect of climatic, operational and design parameters on its performance. One of the most important of the operational parameters that has received a considerable attention in the literature is the brine depth. This paper reports indoor experimental investigations on the effect of brine depth on the productivity and efficiency of the solar stills at four different brine depths of 1.5, 2, 4 and 5.5 cm. Indoor tests were used by simulating the solar input by proper electric heaters located at the bottom of the still for heating the water contained in the basin of the still. The present study validated the decreasing trend in productivity with the increase of brine depth and showed that the still productivity could be influenced by the brine depth by up to 24%.