The invention provides an insertion and connection terminal box and a high-precision manufacturing method of the insertion and connection terminal box to solve the problem that according to an existing terminal box production process, the coplanarity precision requirement is difficult to meet and the widths of protruding ribs are difficult to control. The insertion and connection terminal box comprises a box body which is of a vertically overlapped structure, wherein one lateral side of the box body is a bent edge, the other lateral side of the box body is an overlapping edge, the box body is provided with two protruding rib structures which are horizontally symmetrical, the left side of the box body and the right side of the box body are provided with a plurality of coplanarity measurement points, and the coplanarity of the box body is controlled within 0.035. The high-precision manufacturing method of the insertion and connection terminal box includes the steps of firstly, punching positioning holes; secondly, shearing a knife edge on one side of each protruding rib, and cutting off, supplementing and correcting the knife edge; thirdly, conducting the band tearing and folding process; fourthly, conducting the 45-degree pre-folding process; fifthly, conducting the 90-degree pre-folding process; sixthly, conducting the 135-degree pre-folding process; seventhly, conducting the flattening forming process; eighthly, conducting the adjusting process, wherein the fourth step, the fifth step and the sixth step are executed step by step. According to the insertion and connection terminal box and the high-precision manufacturing method, by improving a punching die and adding the supplementing, correcting and cutting-off process and the multi-stage pre-folding process, product accuracy and product quality are improved.