An internally emulsified polyurethane dispersion, which is prepared by using a combined chain extender system of a hydrophilic amino siloxane compound and a polyetheramine compound, is provided. The internally emulsified polyurethane dispersion can be used to prepare a synthetic leather product having good anti-stickiness, wrinkle resistance, color fastness and superior mechanical properties. A laminated synthetic leather article prepared with said internally emulsified polyurethane dispersion as well a method for preparing the synthetic leather article are also provided.