Background: Benign prostatic hyperplasia (BPH) is frequent disease affecting Up to 50% of men over the age of 50. Prostate cancer (PC) is the fourth most common cancer worldwide and the seventh in Egypt. Cyclin D1 belongs to D-type Cyclin family involved in regulation of cell cycles in driving G1 to S phase. Alcian blue is a mucin stain, playing important roles in adenocarcinomas. Aim: To evaluate the significance of mucin stains and Cyclin D1 expression in BPH and PC and assess the diagnostic and prognostic roles of both in examined prostate lesions regarding the available clinico-pathological data. Material and methods: This is a selected retrospective study performed on 70 different cases included (24) BPH, (36) PC and (10) normal prostate. Clinico-pathological characteristics of examined cases were correlated with IHC of Cyclin D1 and alcian blue special histochemical stain. Results: There was a significant statistical correlation between Cyclin D1 score in studied cases regarding serum PSA, Gleason score, group and perineural invasion and a significant statistical correlation between alcian blue expression in studied cases regarding serum PSA and Gleason group and score, with significant statistical correlation between Cyclin D1 score and alcian blue. Conclusion: Cyclin D1 and alcian blue have a diagnostic role through differentiation between BPH and PC. Also, alcian blue has a prognostic role being correlated with high Gleason scores and with high PSA level.