To provide a pipe connecting structure of a fluid actuator which can simply connect a fluid pipe to the cylinder body of a hydraulic pressure actuator in one touch fashion.

A connection part is provided with annular protuberances 21a, 21b and an annular groove 21c on the fluid pipe 20. A boss portion 12 is provided with a pair of elastic clip attaching grooves 12c and a pair of positioning walls 12d on the same plane. An elastic clip 30 is provided with a pair of elastic legs 30a inserting into the elastic clip attaching grooves 12c and a positioning piece 30b which positions the elastic legs 30a by joining the elastic legs 30a and simultaneously abutting them to the outer peripheral wall of a positioning wall 12f. The elastic legs 30a are provided with a pair of spring portions 30c which form by bending in a direction of approaching each other from both ends of the positioning piece, a pair of removing prevention portions 30d which prevent the fluid pipe 20 from coming off by fitting in the annular groove 21c and a pair of index pieces 30f which bend in direction mutually spacing apart from the tip portion of the removing prevention portions 30d and with which a tip portion 30e protrudes from the outer periphery of the boss portion.