The invention discloses a sponge city planting soil green belt field permeability coefficient testing device, which comprises an upper sleeve, a lower sleeve, a precipitation system and a water levelmonitoring system. The upper sleeve is connected with the upper end of the lower sleeve, and the lower sleeve is buried in the planting soil. The precipitation system comprises a precipitation spray head arranged above the upper sleeve, and the precipitation spray head is externally connected with a water source. The water level monitoring system comprises a water level meter arranged at the bottom of the upper sleeve, and the water level meter is connected with a data acquisition device outside the upper sleeve. By aiming at the sponge road structure of the planting soil and broken stone green belt, the device can be used to test the permeability of the planting soil at different periods on site and provide basic data for evaluating the long-term working performance of the sponge road structure of the planting soil and broken stone green belt.