A coaxial multicore receptacle is provided which has a plurality of ground pins set upright on an insulating substrate and arranged in a matrix pattern, a plurality of signal pins set upright on the substrate each being located at the center of each box of the matrix pattern, first metallic lattice boards provided perpendicularly to the substrate each being positioned correspondingly to and above each column of the ground pins, and second metallic lattice boards provided perpendicularly to the substrate each being positioned correspondingly to and above each row of the ground pins. The first and second lattice boards cross one another orthogonally to define angular coaxial contact insertion holes surrounded by the boards and arranged in the matrix pattern. Each of the first lattice boards is formed with notches in the end portion on the side of the substrate to provide ground pin contact springs which are in elastic contact with the corresponding ground pins. As a coaxial contact is inserted into one of the coaxial contact insertion holes, a center conductor of the coaxial contact comes into contact with the corresponding signal pin.