Background: Menstruation is a normal physiological phenomenon that indicates the sign of motherhood and continuation of generation. Knowledge and awareness about menstruation among males is equally important to overcome the negative beliefs and ill menstrual health of females. Objective: To assess the knowledge and beliefs regarding menstruation among males at Chandernagar, Dehradun, Uttarakhand, India. Methodology: Quantitative research approach with descriptive design was used to assess knowledge and beliefs regarding menstruation among males. A total of 500 men above the age of 18 years were included in the study by using consecutive sampling technique. The study was conducted for a period of two months from 1st January 2022 to 28th February 2022. The data was collected for 6 days in a week. The Self structured questionnaires to assess Knowledge and Belief of men towards menstruation were used for data collection. Results: The mean age of study participants was 40.63 ± 11.58. The result of present study reveals that most of the subjects (approx. 41%) had poor and intermediate level of knowledge and rest of the subjects (17.6%) had good level of knowledge. Most of the subjects (81.2%) had negative belief and the remaining subjects (18.8%) had positive belief towards menstruation. A strong positive correlation (r=0.04) was found between knowledge and belief towards menstruation among males at p value = 0.01. Conclusion: These findings highlight the need to improve knowledge and to erase negative mentalities regarding menstruation among males to improve health of the women and girls over the globe.