This work is concerned with the influence of weather parameters on hydroelectric power generation in the Mosul dam/in Iraq. The investigation was done using specific parameters such as rainfall, and temperature, with the amount of power generated during the last 29 years from Mosul hydropower station. The studies tested the relationship of weather parameters such as rainfall, and temperature with the amount of power generated using multiple linear regression. The pattern of each parameter within the time period of the study was obtained based on the use of collected data. The results showed that the value of the correlation coefficient between rainfall and temperature is 0.9, which confirms that they have a strong relationship with the rate of generated power. The research found an empirical equation between meteorological elements and Hydropower generation. Iraq hydrology is projected to undergo changes causing adverse effects from climate changes in terms of variation in rainfall and variation of temperature, which is expected to have a direct impact on hydropower.