Abstract: Objective To identify PDZ domain containing proteins interacting with PTEN and its characterization with NHERF-1 by proteomic analysis. Methods The interactions between PTEN and PDZ domain containing proteins were screened with PDZ protein array, and the novel one was then identified with GST pull-down and co-immunoprecipitation assay. Results Using a PDZ protein array, we found PTEN　binding with NHERF-1. The interaction of PTEN and NHERF-1 was further characterized by GST pull down assay, and demonstrated that PTEN associated with NHERF-1 via the binding of PTEN carboxyl-terminal with the PDZ domain 1 (PDZ1) of NHERF-1. The last four amino acids (I-T-K-V) of the PTEN were the key determinants of this interaction as mutation of any of the four amino acids to alanine resulted in markedly reducing association of PTEN with NHERF-1. In addition, full-length of PTEN robustly associated with NHERF-1 was also determined by co-immunoprecipitation experiment in cos-7 cells. Conclusion The interaction of PTEN and NHERF-1 was identified both in vitro and in cells. PTEN/NHERF-1 association was mediated via the binding of PTEN carboxyl-terminal with the PDZ1 of NHERF-1, and the last four amino acids of the PTEN carboxyl-terminal were important for PTEN/NHERF-1 interaction.