Objective To make sure the mutation sites of simian immunodeficiency virus (SIVmac239) resistance to 9-(2-methoxy propyl phosphate) adenine (PMPA), to guide the using of SIV/rhesus monkey model in the evaluation of HIV-1 drug. Method Rhesus macaque (RM) were infected with a RM-adapted SIVmac239 strain, were treat with PMPA. And plasma viral load and peripheral CD4 T cells was measured at different time points. Then the drug sensitivity of the virus strain was detected using CEMx174 cells. At last, we screened the mutation sites of rt gene from the virus strain by single genome amplification. Results PMPA treatment can’t effectively reduce the plasma viral load and peripheral CD4 T cells count had no significant chance. Drug sensitivity experiments confirmed that the virus strain is of insensitive to PMPA. Sequence alignment found that S205L and M502I of viral rt gene may affect PMPA sensitivity. Conclusions This study provided some information for the rational use of SIV/rhesus monkey model and clinical treatment of HIV-1.