Introduction: Semen parameters, especially sperm count, concentration, progressive motility and volume have been said to be diminishing over time among men in developing countries like India. Aim: To compare the semen parameters (semen concentration, normal forms, progressive motility and defects) of sub-fertile males visiting ARC fertility Centre in Chennai. Materials and Methods: This cross-sectional study was conducted in Advanced Reproductive Care, Inc. (ARC) International Fertility and Research Centre located in Chennai, Tamil Nadu, India, from the period of January 2015 to December 2019. Total 50 semen samples were selected randomly each year bringing the total to 250 samples which were included in the study. Masturbation was the major method of semen collection. The semen was analysed for the various semen parameters like semen concentration, normal forms, progressive motility and defects in the laboratory under microscope on wet preparation of slides as per the standard guidelines. The various semen parameters along with the age of the participants were entered in Microsoft excel and analysed by Statistical Package for the Social Sciences (SPSS) version 22.0. Results: Total 250 semen reports were included in the study. They belong to age group of persons between 20 to 60 years. More than half of them were 30 to 40 year for all the five years. It was found that there was a statistically significant mean difference among progressive motility (25.14±16.37 in 2015 to 17.30±11.41 in 2019; p-value=0.009), semen concentration (78.1±61.15 in 2015 to 65.96±57.85 in 2019; p-value=0.001) among the semen samples over the years. There was a decreasing trend with the semen parameters being lower than optimal over the years. Conclusion: The study findings suggested that there is a decrease in semen parameters over the years and further studies have to be carried out to find the various environmental and lifestyle factors which could be responsible for the same.