The study was conducted to determine if the drainage network's fractal dimension could be used to classify the resistance of three geological formations in Iran's Yazd-Ardakan catchment. The study also compared the results of the fractal dimensions method with those of the MPSIAC, Feyznia, and Selby methods. There was a significant difference in the drainage network's mean fractal dimension among the three geological formations, with Taft limestone having the lowest fractal dimension (1.149) and the Kahar shale and sandstone formation having the highest (1.207). The MPSIAC and Feyznia methods classified the Shirkuh granite and Taft limestone formations as resistant, while the Selby method and fractal dimensions of the drainage network classified the Taft limestone formation as resistant and the Shirkuh granite formation as moderate. The fractal dimensions of the drainage network were found to correlate significantly with morphological parameters and geological formation sensitivity. In comparison to more resistant formations, more sensitive geological formations were found to have higher fractal dimensions and significantly different drainage network morphologies. This indicates that lithology plays a significant role in the development of drainage networks. In this study, fractal dimensions were effective in classifying and separating the Kahar sandstone and shale, Taft limestone, and Shirkuh granite formations with 93%, 78%, and 75% probabilities, respectively. The study's findings suggest that fractal analysis is a valuable and cost-effective tool for assessing geological formations' resistance to erosion and environmental factors compared to more time-consuming and expensive methods such as field surveys or laboratory analysis.