This chapter investigates the global potential distribution of three entomopathogenic fungi, Cordyceps militaris, Cordyceps tenuipes, and Ophiocordyceps nutans, using ecological niche modeling via MaxEnt. Habitat suitability was predicted under current environmental conditions based on occurrence data from global repositories, literature, and expert records, integrated with a suite of biotic, climatic, and environmental variables. The resulting habitat suitability maps revealed distinct biogeographic patterns, strongly influenced by specific covariates. Notably, host suitability emerged as the primary driver of the distribution of C. militaris and O. nutans, accounting for the highest variable contributions (74.2% and 41.2%, respectively). Among bioclimatic variables, precipitation of the driest month (bio_14) consistently influenced all three fungal species. C. militaris exhibited high suitability in temperate regions, closely emulating its host distribution, while C. tenuipes displayed a broader potential range across humid environments. O. nutans showed a highly restricted potential distribution concentrated in East Asia, despite a wider potential range for its hosts. Five climatic covariates (bio_14, vapr_02, srad_10, vapr_08, and srad_07) consistently emerged as key determinants across the fungal and host models, emphasizing the importance of dry-season moisture availability and seasonal insolation. These findings highlight the critical role of host availability and specific climatic factors in shaping the global distribution of these entomopathogenic fungi, providing valuable insights into their ecological niches and potential responses to environmental change.