The amount of generated electricity by photovoltaic fixed panels depend on tilt angles so must be identified correctly and accurately to increase the rates of solar radiation falling on them in this research were the optimal tilt angle of solar panels on locations of all Iraq provinces monthly and annually by locating a accurate GPS location depending on Google Earth program and then determining the values of the optimum tilt angles using the program in the NASA website. Has been found that the optimal tilt angle range between 28.3 for the province of Basrah as a minimum tilt angle with the horizon and 34.5 for the province of Dohuk as highest tilt angle with the horizon. Has been shown that the difference between the inclination angles optimal annually to Iraq's provinces on the horizon for the solar panels and between latitudes for those provinces almost invariably ranging from 2 to 3 degrees. It was noted that the difference between the monthly optimal tilt angles of provinces is ranging from 1 to 8 degrees.