Connector set and method for assembling connector set

Provided is a connector set and a method for assembling a connector set, in which a first connector and a second connector can be easily connected. A connector set according to the present invention is characterized in that: the first connector includes a first body that has a first positioning part, and a first retaining member that has a first press-fitted part that faces the lower side; the second connector includes a second body that has a second positioning part, and a second retaining member configured so as to be capable of moving relative to the second body between a first position and a second position, the second retaining member having a second press-fitted part that faces the upper side; the first positioning part and the second positioning part engage with one another to position the first connector and the second connector in the lengthwise and lateral directions; and the first press-fitted part and the second press-fitted part are press-fitted when the second retaining member is in the second p