Background. Circadian and circannual cycles of testosterone (T) in men are known. The results of our previous study have shown indices for the existence of a male circalunar cycle of T similar to the female one. Objective. The purpose of this study was to investigate possible infradian rhythms of salivary T in young healthy men. Subjects & Methods. Saliva samples from 31 healthy men (18–25 years of age) were collected every second day (for 1 month) and every third day (during the following 1.5 months). T levels were determined by radioimmunoassay. Data were statistically analyzed for infradian rhythmic changes using two different methods: moving averages – zones of extremes, and analysis of rhythmic variance. Results. The data showed rhythmic variations with 2 different infradian periods. The differences between extreme values of the circatrigintan (period of 30 days) and circavigintan (period of 20 days) cycles were found to be highly significant (p < 1E-9; p < 1E-8). Conclusion. We believe that this is the first study demonstrating the existence of circatrigintan and circavigintan rhythms of testosterone in human males. Our findings might have implications in human physiology and pathophysiology.