Although vitamin D deficiency is one of the most common health problems throughout the world, conflicting information exists on the potential association between serum vitamin D levels and semen quality. Currently available data identifies that vitamin D has a vital role in reproductive process as it affects sperm motility. This study was done with the rationality to evaluate the association between serum vitamin D levels with asthenozoospermic males. This cross-sectional analytic study was conducted on 314 men who attended the Department of Reproductive Endocrinology and Infertility, Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh July 2018 to June 2019. Considering the inclusion and exclusion criteria all participants were categorized into two groups; Group I included 157 asthenozoospermic male and Group II included 157 normozoospermic male according to World Health Organization 'strict' criteria 2010. Participants completed the questionnaires after they had agreed on a informed consent. Blood and semen samples were obtained for assessment and all data were adjusted for age, body mass index (BMI), total motility and progressive motility. Vitamin D levels were classified according to the Endocrine Society guideline. Statistical analyses were carried out by using the Statistical Package for Social Sciences version 22.0 for Windows (SPSS Inc., Chicago, Illinois, USA). The results showed that the mean vitamin D level was 16.63±5.54ng/ml in asthenozoospermic group and 19.83±5.33ng/ml in normozoospermic group. The mean vitamin D level was significantly (p<0.05) lower in asthenozoospermic group. It was noticed that 86.6% patients had vitamin D deficiency (≤20ng/ml) in asthenozoospermic group compared to 56.7% in the normozoospermic group. The study found that low vitamin D was associated with a fivefold increased risk of developing asthenozoospermia at 95% CI (2.74-8.99). Moreover, there was a positive significant correlation (r=0.285; p<0.001) between serum vitamin D level with total motility and progressive motility (r=0.232; p<0.001). Hence, the study suggests a significant association between asthenozoospermia and low vitamin D levels. However, clinical trials are warranted to further reinforce the findings.