Ectomycorrhizal fungi has long been known as benefit microorganism for plants, because the fungi supply nutrients and water from soil to their hosts. But ectomycorrhizal fungi are very sensitive to environmental change of their habitat, thus can be used as bioindicator. One of the change that influence on their presence is forest fire that kill the trees as their hosts. Forest fire is almost occur every year in the dry season in Indonesia, not exception Kutai National Park (KNP), where the fire comes from the society gardens surrounding it. This study aimed to determine species diversity and dominance of ectomycorrhizal fungi on the after burned (Prevab) and unburned forests (Sangkimah). The results showed that the number of species of ectomycorrhizal fungi at Prevab were 12 species and 37 individuals, while at Sangkimah there were found 34 species of 87 individuals, this meant that the numbers of species and individuals of fungi at Sangkimah were more than at Prevab. However, based on biodiversity index, at both locations were low (H'<1), respectively was 0.51528 at Prevab and 0.50233 at Sangkimah. At Prevab, species of fungus with high levels of dominance was Clavulina sp., moderate level of dominance were Mycena pura, Coprinus atramentaria, C. comatus and Russula decolorans, whereas other species were in the level of low dominance. At Sangkimah, fungi with a high level of dominance was Clitocybe sp4, moderate level of dominance were Leucocoprinus flos-sulfuris and Cantharellus sp3, whereas other species were in the level of low dominance.