A terminal-fitted retainer (20) includes terminals (50) that have recesses (57) provided on outer peripheral surfaces thereof and to be inserted and accommodated into terminal accommodating chambers (38) formed in a housing (30) from behind. A retainer (70) is mounted into the housing (30) while retaining the terminals (50). The retainer (70) includes terminal holding portions (74) for holding the terminals (50) by being fit into the recesses (57) and thick portions (78) to be accommodated into clearances formed between the terminal holding portions (74) and either front or rear surfaces of the recesses (57) in a front-back direction.