In this study, the performance of the single slope solar still is improved by floating the porous wick material with different geometries in the basin. The jute cloth is used as the porous wick absorber, which is floated in the basin by the thermocol material. Three modified solar stills (named by MSS) with three absorber's geometries are considered. The porous wick layers with flat, triangular-shaped, and semicircular-shaped tooth are used as the absorber surface in MSS-1, MSS-2, and MSS-3, respectively. The productivity and performance of these modified solar stills are compared to the conventional single slop solar still (named by CSS). The theoretical method is used to perform the performance analysis of these solar stills. The results showed that all three MSS devices produce more than 0.6 kg.m(-2).hr(-1) of freshwater during most of its operating hours, while the CSS device produces this amount of freshwater in only the last few hours of its operation. MSS-3 device produces the most daily yield among the other modified stills, which produces 65% more daily yield in comparison with the CSS device.