Objectives This study was performed to research the biological change after walking program in forest according to Sasang constitution. Methods Twenty four applicants are involved in this study. They were classified into three groups(Soyangin, Taeeumin, Soeumin) by QSCC II and divided into two groups(roadway, forest path) by place. And then they participated in walking program on March 31 in 2012. We performed before and after measurements, including active oxygen, biochemical test(BC), and stress hormones. Results Cortisol decreased in the entire group after walking program, which means the effect of relaxation. Glucose reduced in Soyangin group while increased in Taeeumin and Soeumin group after the program. There was no correlation in the test results between Sasang constitution and walking place. Conclusions Walking program has shown most efficacy in relaxation. However a single positive result within this study should be carefully interpreted. In the future, well-designed studies for Sasang constitutional walking program are needed.