From September 30 to October 2, 2022, the activities of the Matsutake Mountain Development Cooperation Volunteers were held for the fourth time in Iwaizumi Town, Iwate Prefecture. About 20 members of the JOCV, young and old (4 university students) participated, and participants came from as far away as Tokyo and Saitama Prefectures. This time, we marked the areas where the occurrence of matsutake mushrooms had been confirmed, and focused on the maintenance of the surrounding area (Photo 1). What is noteworthy is that we were able to confirm the occurrence of matsutake mushrooms in the area where we maintained it last spring (Photo 2). Since we were able to confirm the occurrence in a little over a year after the maintenance, we can expect future results. On the last day, they participated in a Shinto ceremony at Matsutake Shrine (Photo 3) and had a reunion next spring.