Within the context of this study conducted at Alaçam Mountains located between Balıkesir – Kütahya; we intended to find out the effects of altitude, slope, aspect, stand age, canopy closure and site productivity on pH characteristics of lichen contented in forest floor and the relations between changing pH values. With this aim totally 115 sampling points were sampled from composition of 5 altitude levels, 3 slope levels, 4 main aspects, 3 age classes, 3 closure degrees and 5 site productivity levels. According to achieved results average pH value of 115 sites is 4.68 with 4.39 and 5.52 minimum and maximum ranges. pH values of forest floor lichen according to aspect and altitude differs from each other significantly while stand properties could only cause different but statistically insignificant values. As conclusion stand properties did not affect the pH of forest floor lichen nevertheless aspect and altitude have slight but significant effect.