Background and Objectives: Stress can disrupt homeostasic balance within the organisms. Chronic stress can have damaging effects on the whole organism. The present study aimed to throw more light on the molecular, immunological and histological alterations in adult albino rat’s testis subjected to chronic stress and to demonstrate whether the potential chronic stress‑induced testicular alterations could be ameliorated by astaxanthin or not. Materials and Methods: Forty healthy adult male albino rats were used in this study, they were assigned as 3 main groups: Group I (Control group) which are subdivided into two equal groups, Group II (stress group) rats were restrained for 1 h and after 4 hs they are forced to swim for 15 minutes every day for 6 months, and Group III (protective group) rats were subjected to stressors as previous group in concomitant with daily administration of astaxanthin (25mg/kg b.w.) dissolved in 1ml normal saline in a single daily dose orally in a single daily dose. Blood samples and testicular tissues were collected and assayed for histological, immunohistochemical and biochemical changes. Results: The results of the present study demon¬strated that there were degenerative changes in spermatogenic and Sertoli cells of stress group and were associated with statistical significant reduction in height of germinal epithelium, Ki-67 and vimentin immunoexpression.These changes were observed to be reduced in astaxanthin protected group. Also, there was a decrease in serum testosterone levels in stress group, which were normalized after astaxanthin administration. Also, stress significantly increased the serum levels of malondialdehyde, and decreased levels of total antioxidant capacity TAC. Conclusions: This study concluded that astaxanthin has beneficial protective effects against the deleterious effects of chronic stress on the testis. Therefore, it may be a suitable nutrional supplement in alleviating some negative aspects of chronic stress effects on testis.