<p>There is no consensus on which diet best for improving male reproductive health and published studies on the effect of diet on sexual function and semen quality are limited. The aim of this study was to investigate the effect of intervention based diet, namely Persian Medicine Diet (PMD) and Mediterranean Diet (MD), on sexual function and semen quality parameters. In this single blind, randomized controlled clinical trial, 159 male patients with oligoasthenospermia aged between 18 and 45 years were enrolled and divided into three groups of 53 people each. The patients were randomly assigned to either PMD or MD intervention and control groups for two months between July 2022 and February 2023 in Shiraz, Iran. To evaluate the outcomes, we used the International Index of Erectile Function (IIEF-15) questionnaires that included five subscales and semen quality parameters. The mean age of the participants was 30.87 ± 6.55. Our analysis showed that total score of IIEF was higher in the PMD intervention (<i>P</i> ≤ 0.001). In addition, the PMD intervention showed a higher average difference in erectile function and intercourse satisfaction subscales, respectively (<i>P</i> ≤ 0.001, <i>P</i> ≤ 0.003). However, MD intervention showed a higher average difference in orgasm function subscale (<i>P</i> = 0.053). Additionally, in semen analysis, the study showed that MD intervention improved statistically. Also, semen count, sperm motility, and morphology difference improved significantly (all <i>P</i> ≤ 0.001). To improve infertility, PMD and MD interventions could positively impact male sexual function and semen quality parameters in infertile mess. Further studies with larger sample sizes and longer durations are needed for conclusive results.</p>