Regulation of the deposition morphology after sessile drop evaporation has numerous applications and potential benefits. The drop evaporation of particle suspension with polystyrene particles and sodium dodecyl sulfate (SDS) was experimentally observed and analyzed. The effect of SDS with a concentration of 0wt%~1wt% on the evaporation process of polystyrene particle suspension and the deposition morphology after evaporation was studied. The results demonstrated that the droplet contact angle decreased nonlinearly with the increase of SDS concentration. When SDS was added, spontaneous spreading driven by surface-tension gradient occurred. It was found that the maximum spread coefficient was positively correlated with SDS concentration. The spreading process took only 1/5~1/3 of the total evaporation process time. The gray level co-occurrence matrix (GLCM) was used to analyze the effect of adding SDS on the deposition morphology inside the coffee ring. The SDS could not only regulate the ring width, but also reduce the aggregation of particles in the middle of a deposition, and the deposition was more uniform (the most obvious when the concentration of SDS was 0wt% compared with 0.1wt%). Marangoni flow in the droplet would become more ferocious as SDS concentration rose, and the ring grew broader. There was an upper limit for SDS to regulate the ring width of the annular deposition, as the annular deposition was not readily apparent when the concentration of SDS was higher than 0.75wt%. Most of the particles were uniformly distributed throughout the entire deposition area, forming a disc-like deposition. The maximum percentage of annular deposition area for particles were 58.6% for diameter of 5.7 μm and 44.6% for diameter of 10 μm. It demonstrated that SDS affected the deposition pattern of particles of various sizes in distinct ways.