Most of the forest lands lying on rugged mountainous areas create complex logging problems in Turkey. In the process of logging, a vvrong vvay follovved not only causes wasting of more power, money and time, but also obtaining less amount of wood material and damage forest soils. In tfais study, logging operations done nsing Koller K 3Ö0 forest skyline in the mountainous land of ikizdere district were evaluated. Average output measured vvith Koller K 300 was 5.490 m3/h for conifers at 180 m distance vvith 40% slope. Volüme of transported material was 0.811 m3 at every turn. It vvas also found out that the loading time have an important place in total turn time and was 46.07 %. Average vvorldng hour per machine, vvhich was found low in theregion, has to increase up to 8 hours at least for operators and vvorkers.