Aquaculture plays a significant role in fulfilling the nutritional requirement of a growing population and contributes to the economic growth of Nigeria. However, catfish farming in Nigeria has faced various challenges, with diseases being a major setback. This retrospective study from 2018-2020 aims to review the commonly isolated bacteria and fungi organism of catfish from submitted samples and the seasonal variation of cases from our laboratories in Ogere, Lagos, Asaba, Ibadan and Abuja. A total of 357 cases were recorded. The most prevalent recorded was Vibrio parahaemolyticus (151 cases; 42.3%); followed by 110 cases (30.8%) of Aeromonas hydrophila. Fungal isolates of Aspergillus flavus, A. niger, and Candida albican (3.9, 2.5, and 3.6%, respectively) were also made. A comparison of the rainy season cases (196 cases, 54.9%) was statistically significantly different (p＜0.05; Chi-square analysis) from dry season (161 cases; 45.1%). Overall, the retrospective study provides valuable insights into the bacterial and fungal pathogens isolated from catfish in Nigeria. However, these findings also highlight the need for improved disease detection and correlation with other culture issues (e.g. water quality and parasite infestations), better disease diagnosis techniques, and management strategies. With the help of the American Soybean Association/World Initiative for Soy in Human Health (ASA/WISHH), Animal Care Services is both receiving and conducting training to better detect causative problems that lead to mortalities in the Nigerian catfish industry.