By using the OLS model, an equation for the rate of decomposing wood by a variety of fungi was established. We analyzed the effects of various fungi in the experimental data under different temperature and humidity. Based on the growth performance of different fungi at different temperatures and humidity, we use the method of systematic cluster to divide the fungi into 5 categories, and introduce competition levels as the viability of different species of fungi. We have established a logistic model that introduces competition levels to obtain a fungal habitat model. The fungal habitat model includes predictions about the relative advantages and disadvantages for each species and combinations of species likely to persist, and do so for different environments including arid, semi-arid, temperate, arboreal, and tropical rain forests.