A wiring unit 1 includes a plurality of crimping terminals 2; and a plurality of insulating plates for holding said crimping terminals. The insulating plate 2 has a terminal groove 5 concaved from the surface, an accommodating portion 6 and a through-hole 7. The accommodating portion 6 is formed in concave from one of a pair of partition walls 9a and 9b constituting the terminal accommodating groove 5. The through-hole 7 passes through the insulating plate 2 and communicates with the accommodating portion 6. The crimping terminal 3 is composed of the electric-wire connecting portion 13 on which the electric wire is crimped and an electric-wire connecting portion 14. The insulating plates 2 are stacked while holding the crimping terminals 3. The electric contact portions 14 of the crimping terminals 3 held in the adjacent lower and upper insulating plates 2 are not superposed. The electric contact portion 14 of the crimping terminal 3 held in the lower insulating plate 2 is accommodated in the accommodating portion 6 via the through-hole 7 of the upper insulating plate 2. In this configuration, the wiring unit can be miniaturized.