Abstract: This paper evaluates the different empirical models used for the estimation of solar energy irradiation on tilted surfaces. For this purpose, three isotropic and the same number of anisotropic sky models were employed by using monthly mean solar radiation and weather data of Kuching, Sarawak, Malaysia. The tilt angle was fixed at 11ºS towards the equator for optimization of incoming solar radiation from the sun during the worst months of the year from October to March due to overcast skies. It was discovered that the Reindl et al. model estimated the highest amount of incident solar energy in the whole year and Badescu model established the lowest among all isotropic as well as anisotropic models, whereas, Liu and Jordan model performs well at the time of bad weather conditions. It is concluded that the selection of Liu and Jordan model could be useful for the prediction of solar energy irradiation on tilted surfaces in the study area, where the weather is mostly cloudy.