The plant sulfate transporter proteins play important roles in transport and absorption of sulfate. It has been demonstrated that the members of this family in plants may be classified into 5 main groups. In the present study, we found the statistical evidence of shifted evolutionary rate between groups that contributed to functional divergence of this family in plants. Furthermore, evolutionary analysis illustrated that positive selection played important role during the long period of evolution for this family, and Sulfate_transp and STAS domains had co-evolved in the evolution of proteins containing both domains.