The present invention relates to a wire clamp for a cross pipe, and more specifically, to a wire clamp for a cross pipe, which is bound to the intersection part between each horizontal pipe and each vertical pipe constituting a foundation frame of a vinyl greenhouse so that the structural solidity of the frame can be enhanced. According to the present invention, the wire clamp for a cross pipe is formed into a ring shape by bending a predetermined length of metal wire into a fixed shape and is bound around crossed multiple vertical pipes and multiple horizontal pipes so the vertical pipes and the horizontal pipes can be fixed. The wire clamp has a hemispherical cross section structure, thereby longitudinally forming a spherical surface which exhibits stress corresponding to an external force and a plane surface to enlarge the area of a part which touches the outer surface of each pipe. A first compression part is formed by distorting the longitudinal middle part of the wire clamp into a reversed U-shape, and is curved to surround the upper circumferential part of each vertical pipe arranged on the upper side of the wire clamp so as to push and fix the vertical pipe downwards. Both longitudinal sides of the wire clamp are extended in the same direction due to formation of the first compression part. A second compression part is formed by distorting the middle parts of the both longitudinal sides into a U-shape, and is curved to surround the lower circumferential parts of each horizontal pipe arranged on the lower side of the wire clamp so as to push and fix the horizontal pipe upwards. The end parts of the both longitudinal sides extended in the same direction from the first compression part are bent to face each other so as to be overlapped in line. A third compression part is formed by distorting the end parts of the both longitudinal sides into a reversed U-shape, and is curved to further surround the other upper circumferential part of the vertical pipe so as to
