Abstract: In recent years，subsoiling as conservation tillage has been widely applied throughout the country. In view of the site conditions such as slopes，tea gardens and greenhouses that conventional tractors can not go to due to the limitation of terrain and agronomy，several experiments had been carried out on the power，walking mechanism and subsoiling shovel of the narrow mini loosening machine，and a new mode of subsoiling operation with 7.35 kW miniature diesel engine and rubber track walking mechanism had been explored. Field experiments showed that qualified rate of subsoiling depth，qualified rate of adjacent row spacing and lost tillage met relevant industry standards of subsoiling operation quality. It provides an important reference for further research on narrow width mini loosening machine and promoting deep loosening operation in hilly and mountainous areas，tea gardens and greenhouses.