An electrical connector includes an insulating housing (1a) including a pair of retaining spacers (1b) embedded therein and a number of terminals (2). The insulating housing has a base portion (11) with a concaving room (110) and an engaging portion (12). The terminal (2) defines a retaining portion (21) retained in the base portion, a contacting portion (22) projecting in the engaging portion and a leg portion (23). The retaining spacers are received in the concaving room and press against the retaining portions of the terminals.