Background: Prostate cancer is one of the most frequent malignancies worldwide. Mucin 4(MUC4) is a transmembrane mucin that is contributed in cell signaling events that guide the proliferation of cells. Insulin-like growth factor 2 (IGF2) messenger RNA binding protein 3 (IMP3) has been linked to tumorgenesis and progression of many cancers. Aim: This study aimed to evaluate MUC4 and IMP-3 expression in different prostatic lesions and to relate the results with clinicopathological data. Material and method: This retrospective study examined 40 cases including 10 cases of benign prostatic hyperplasia (BPH), 6 cases of high-grade prostatic intraepithelial neoplasia (HGPIN) and 24 cases of prostatic adenocarcinoma (PCa) . MUC 4 and IMP-3 were used for immunohistochemistry. Results: MUC4 was detected in (100%) of BPH & HGPIN cases and (16.6%) of prostatic carcinoma. IMP3 expressed in (100%) of prostatic cancer cases and expressed in(10%) &(16.7%) of &HGPIN respectively. A significant statistical correlation between IMP3expression and stage, Gleason’s grade, pre OP serum PSA level>10ng/ml, --capsular and perineural invasion(P |