J-SACL was conducted on a total of eight forestry workers (four females and four males) to clarify the physical, psychological and social stress states of such workers for contributing to the spread of forestry worker education and forestry technique. The investigation revealed that stress levels of the participants were low, while arousal levels were high. Stress levels were significantly lower than those of general adults and the risk of stress-related diseases was low. Stress levels measured after forestry operations tended to be lower than those before those operations. Although the existence of psychological stress from mechanized work was pointed out in previous studies, there were no such signs in our work. This may be because the workers were not only affected by mechanized operations but also by other manual labor during the study periods. A comparison of our results with those in other fields shows that stress levels of forestry workers in this study were equivalent to those of urban college students who had undergone stress relaxation training.