In order to increase the moisture permeability of the polyurethane synthetic leather and get comfortable feel of it, in this paper five different porogens such as polyethylene glycol, modified cellulose, carbamide, polyvinylpyrrolidone and wood flour which affected the moisture permeability and mechanical properties of polyurethane microporous films were studied. And the influence of the dosage and difference of porogens were investigated though the moisture permeability, hygroscopic property, mechanical property of polyurethane microporous films, and SEM. The results indicated that the moisture permeability, hygroscopic property, porosity and feel of the polyurethane microporous films were greatly improved. And the moisture permeability, moisture absorption rate and porosity could achieve 1876.81g?mm/(m2?24h)，180% and 7.55% respectively, which increased by 315%，350% and 358% respectively. The polyethylene glycol, carbamide, wood flour had the excellent performance.