The invention relates to a split spacing optimization and selection method for a multi-split wire. The split spacing optimization and selection method comprises the following steps of (1) analyzing an electromagnetic environment according to a voltage level to obtain a wire split spacing selection range which satisfies requirement of an electrical environment; (2) determining several kinds of wire split spacing values within the wire split spacing selection range; (3) analyzing a relation between a subspan oscillation amplitude value and a maximum subspan of the split wire under the wire split spacing valuing condition; (4) optimizing the split spacing values; (5) performing verification on the split spacing values based on a fitting design condition and economical efficiency; and (6) performing iteration on the steps of (3)-(5) repeatedly to determine an optimized split spacing value. By adoption of the technical scheme of the split spacing optimization and selection method, the reasonable wire split spacing can be chosen specific to a circuit condition so as to directly support circuit design and construction.