PURPOSE: To provide the leg tip posture drive device of a leg type moving mechanism which performs ZMP type walking on a ground touching surface having three- dimensional waviness.

CONSTITUTION: A ground touching plate 11 is angularly displaceably coupled to the tip part of a support leg 10 and a pitch direction drive mechanism 15 to perform angular displacement of a ground touch plate 11 in a pitch direction is located between the ground touching plate 11 and the support leg 10. A roll direction drive mechanism 30 to cause angular displacement of the ground touching plate 11 along a roll direction is provided. Further, a pitch direction drive mechanism 15 and load cells 31a-31c to detect a load exerted on the roll direction drive mechanism 30 by the ground touching plate 11 are provided. A control part 32 to control the drive mechanisms 15 and 30 in a direction in which the posture of the ground touching plate 11 follows a ground touching surface according to detecting information from the load cells 31a-31c is provide. This constitution forces the ground touching plate 11 into contact with a ground touching surface T having three-dimensional waviness as a posture adapting itself to waviness is kept and prevents collapse of the posture of the ground touching plate 11 making contact with the ground touching surface.