This research aimed to know the influence of ethanol extract of beetroot (L.) on the number, morphology spermatozoa and testis weighin male mice (Mus musculus) by by exposure to heat. This research was conducted by using Post Test Only Control Group Design. Data was statistically analyzed by using onewayANOVA followed by Duncan Post Hoc Test (P<0.05).The study used 30 male mice aged 2-3 months, weight 20-35 g and were randomly divided into 5 groups with 6 mice each groups. Group K- (negative control) were given distilled water, Group K+ (positive control) is exposed to temperatures of 40 ° C for 60 minutes/day, third group (P1)is exposed to temperatures of 40 ° C for 60 minutes/day and a solution of tuber extract bits dose of 100 mg / kgBB / day, fourth group (P2)is exposed to temperatures of 40 ° C for 60 minutes/day and a solution of tuber extract bits dose of 200 mg / kgBB / day, fifth group (P3) )is exposed to temperatures of 40 ° C for 60 minutes/day and a solution of tuber extract bits dose of 400 mg / kgBB / day. This research lasted for 36 days, at 37 th day all mice were terminated, then the sperm count, morphology spermatozoa and testis weigh was done. The results showed significant differences in the number, morphology of spermatozoa and testis weight between groups (P <0.05). But Duncan's test based on the number and morphology did not show any significant difference. Where the ethanol extract of root beet (Beta vulgaris L.) with a dose of 100 mg / kgBB / day, 200 mg / kgBB / day and 400 mg / kgBB/day can not fix and increase the amount of morphologically normal spermatozoa in mice induced heat for 60 minutes. And testis weight at a dose of 200 mg / kgBB / day and 400 mg / kgBB / day showed a significant difference where the results showed that the ethanol extract of the tuber bit heavy testes capable of repairing damaged by exposure to heat.
