T-cell lymphoma is a rare disease in which T lymphocyte cells become cancerous. These lymphomas account between 10 percent and 15 percent of all cases of Non-Hodgkin lymphoma in the United States. Like the B-cell lymphomas, T-cell lymphomas are classified into two broad categories: aggressive (fast-growing) or indolent (slow-growing) (1). The G1/S checkpoint of the cell cycle is controlled by pRb protein, which functions in its hypophosphorylated form as a negative regulator of growth. p27 (Kip1), a member of CIP/KIP family of cyclin inhibitory proteins, participates in inhibition of forming complexes that allow pRb to phosphorylate and lead the cell into mitosis (2). To analyze the impact of concordant expression of p27 and HTLV-1 infection on a group of tissues with Non-Hodgkin’s lymphoma (NHL). Eighty formalin-fixed, paraffin- embedded lymph node tissues were enrolled in this study; (40) biopsies from Non-Hodgkin’s lymphoma (NHL), and (40) lymph nodes with (unremarkable pathological changes) as apparently healthy controls. Detection of HTLV-1was done by ultra-sensitive version of In situ hybridization method where as immunohisto chemistry detection system was used to demonstrate the expression of P27 gene expression. The HBZ gene of HTLV-1positive –CISH reaction was detected in (45%: 18 out of 40 cases) of Non-Hodgkin lymphoma tissues. No HTLV-1 positive – CISH reaction was detected in healthy lymph nodes tissues of the control group. The differences between the percentages of HTLV-1 detection in NHL tissues and control groups were statistically highly significant (P value = < 0.05). The positive P27-IHC reactions wase detected in 42.5% (17 out of 40 cases) of Non-Hodgkin lymphoma cases. A strong positive correlation was found between the detection, scores and intensity of p27 marker. Significant expressions of both p27 markers as well as HTLV-1 genes in Non-Hodgkin’s lymphoma could indicate for their possible roles both in lymph node pathogenesis and carcinogenesis