The study examined the effects of microclimate on fish production in Ilorin West local government area. The study was conducted to determine fish responses to its microclimate on daily basis at different seasons of the year and also to determine the quality of water for pond fish culture. Experimental research of earthen pond was set up at Atiku Road located in Adewole Housing Estate area for a period of two years which spanned between 2014-2015. Temperature of the pond water was recorded at different depth intervals of 30 cm, 60 cm, 90 cm and 120 cm respectively. The pond water was sampled and analyzed for ammonia, nitrate content, dissolved oxygen, Biochemical Oxygen Demand (BOD), suspended solids, pH, electrical conductivity and turbidity level to determine its chemical properties and reveal the quality of water using standard laboratory methods. The amount of feed consumed was measured on monthly basis. The rate at which fish gained weight was also noted. Both descriptive and inferential analysis of correlation and regression were carried out to find out the strength of relationships between fish weight, feed and temperature. The temperature of the depth of pond water that is most critical for fish production using earthen pond was determined. The study revealed that the average temperature of the water ranges between 26.83 °C and 29.96 °C. The month of January recorded the lowest temperature of 26.83 °C, while the highest of 29.96 °C occurred in the month of February, thus giving the range of over 3 °C per annum. The results also showed that fish does not cluster at 30 cm depth which has the lowest temperature but between the depth interval of 60 cm and 90 cm throughout the seasons.