Hyperlipidemia has been related to sever health outcome include cardiovascular complication, metabolic disorders and infertility. Moreover, obesity has also been linked to dangerous effects on testicular morphology, spermatogenesis and sperm malformation. Many studies using different herbal medicines exert protective and therapeutic effect on the testes, spermatogenesis and fertility in animals fed high fat diet. Objective: this study aimed to find out the protective effect of cinnamon on testes of albino rat fed high fat diet (HFD). Forty adult male albino rats were selected and equally divided into 4 groups. Group 1: animals of this group were fed standard diet. Group 2: rats were fed standard diet and cinnamon "15% weight by weight, w/w" for 8 weeks. Group 3: animals in this group were fed HFD (2% cholesterol, 15 % sucrose, 15% corn, 15% cocoa butter, starch and 4.7% cellulose) for 8 weeks. Group 4: animals in this group were fed HFD and cinnamon. At the end of 4 weeks half animals were sacrificed and the rest of animals were sacrificed at the end of 8 weeks and blood samples were collected to assay the testosterone level. As well as testes were taken and prepared for both histological and ultrastructure studies. Histological examination of testicular tissue of HFD-fed animals revealed many pathological changes include degenerated seminiferous tubules, distorted germinal layers and interstitial tissue appeared degenerated with intertubular hemorrhage. Ultrastructural observations showed severe degenerated features including both different types of spermatogonia and interstitial tissue. On the other hand, both histological and ultrastructural alterations were substantially but not completely protect in obese animals fed HFD and cinnamon for 4 weeks while advanced degree of improvement tissue appeared after 8 weeks of the same treatment. As well as, significantly increase in the level of testosterone was recorded when compared with HFD-fed animals. The present work concluded that cinnamon dietary uptake may improve testicular damage induced by HFD as it has anti-inflammatory, anti-obesity and antioxidant activities.