In an electrical connector wherein signal transmission paths 53 have signal connecting portions 53 C soldered to signal circuit units on a circuit board, ground members 54, 55 have ground connecting portions 54C, 55C soldered to ground circuit units on the circuit board, and the ground connecting portions 54C, 55C are positioned in the arrangement direction of the signal transmission paths 53 between the signal connecting portions 53C of adjacent signal transmission paths, a width range WG between the opposite end locations of the ground connecting portions 54C, 55C of the ground members 54, 55 in the width direction, which is parallel to the mounting surface of the circuit board and perpendicular to the arrangement direction, extends beyond the width range WS of the signal connecting portions 53C of the signal transmission paths 53.