Introduction: The lack of accurate and timely sex education would endanger the physical and mental health of adolescents. Parents play an important role in the sexual education of adolescents, but they meet some challenges especially in Iran. The aim of this study was to describe the experiences and perceptions of parents' challenges of sexual education of male adolescents. Method: This qualitative study was conducted using content analysis method in 2016. Data were collected by semi-structured group interviews with 25 parents of 10-19-year-old adolescents who were living in Ahvaz and selected using purposive sampling method. Data were analyzed by qualitative content analysis. Results: After data analysis, 29 codes, 7 sub-themes (contradiction of parental views, parental confusion, barriers to communication with adolescents, the multiplicity and complexity of the sources of sexual information, cultural taboos, the lack of understanding of the need for sexual education, the missed role of school in sexual education) and one main theme (challenges of sexual education in male adolescents) were obtained. Conclusion: The results of this study show that parents had inadequate skills in communicating with male adolescents, most of which derived from cultural taboos such as shame and hide and fear of breaking divorce between parents and adolescents. Therefore, the parental empowerment for the sexual education of adolescents with institutionalizing formal sexual education in the form of child-rearing practices is essential.