This study aimed to develop an operational system for thinning using a tower yarder newly-introduced from Europe. To that end, the productivity of thinning operations was researched, and the uphill yarding operation under the cable was analysed in this report. The yarding time did not have a clear relationship with the loading volume, and had a high correlation with the yarding distance, thus a prediction relation of the productivity for uphill yarding was able to derive. On the mean yarding distance of 114m and the mean loading volume of 0.69m^3 in this research area, the whole productivity of uphill yarding was 11.5m^3/hour, which was predicted 1.5 times higher than the existing similar tower yarder. It is clear that this newly-introduced tower yarder could be expected to get the higher productivity in the forest condition in Japan.
