To solve a problem that the machine frame of a walking power tiller does not stably straightly travel, is liable to meander and does not give a work finish having a good appearance, because the rotary tilling section is floated or digs into the right or left ridge sidewall, when the walking power tiller having the tilling device is placed in a ridge valley and subjected to a backward travel tilling work along the ridge valley in a state that the tilling device is positioned at the head.

This walking power tiller 5 which has driving wheels 2, 2 disposed on the right and left sides of the lower portion of a transmission case 1 and a rotary tilling device 4 disposed behind the transmission case 1 and in which a driving power is transmitted from an engine 3 installed on a place near to the upper portion of a transmission case 1 and then transmitted into the driving wheels 2, 2 and the rotary tilling device 4 in a distributed state, characterized by attaching a pair of gauge projections 7, 7 to the right and left front portions of the front frame 6 of the machine body in approximately the same width as the outer width of the driving wheels 2, 2, projecting a control handle 8 in the rear portion of the machine frame up to a place above the rotary tilling device 4, and backward traveling the driving wheels 2 of the walking power tiller 5 along a ridge valley D between right and left ridges M, M in a state that the control handle 8 is placed at the head.