Abstract: The effect of casting blast could influence working performance of dragline and cost of production in open-pit.Therefore，to optimize blast parameters was a significant measure to promote the blast effect.Based on fuzzy mathematics theory，the efficient casting rate，coefficient of volumetric expansion，shocking effect and explosive consumption are selected as evaluation factors，and the synthetic evaluation model of casting blast for Heidaigou open-pit coal mine is established.And the effect is evaluated as excellent from analysis of in  situ measurement.The evaluation model's establishment provided an efficient method for evaluating the effect of casting blast for open pit.

Key words: Open-pit coal mine, Casting blast, Fuzzy synthetic evaluation, Blasting effect