The present disclosure relates to the field of epoxide resin, and more particularly to an epoxide with a low total chlorine content and no heavy metal residues, and a preparation method thereof. Disclosed is an epoxide prepared from raw materials including an unsaturated cycloaliphatic compound containing a double bond, hydrogen peroxide, an organic acid compound, a solvent and an alkaline salt; wherein a molar ratio of the organic acid compound to the unsaturated cycloaliphatic compound containing a double bond is (1-1.5):1. The obtained epoxides obtained in the present disclosure have a high purity, a high yield, a low solvent content, low chroma, and a low chlorine and metal ion content; the reaction system is simple, environmentally friendly, safe and controllable, and the production cost is low, which can meet the technical and economic requirements and are suitable for large-scale industrial production.