The invention discloses a polarizing type stereo projector engine which comprises a light source assembly, a light splitting/light composition optical path system and a projection lens. Light beam emitted by the light source assembly enters an inlet of the light splitting/light composition optical path system and is modulated as polarized light beam whose polarization state is vertical to other light beam, and the light beam enters into the projection lens. The light source assembly comprises a first light source, a second light source, a first polarization splitter, a first line polaroid transmitting P-polarized light, and a second line polaroid transmitting S- polarized light. Light beam emitted by the first light source transmits the first line polaroid and enters a first inlet of the first polarization splitter, light beam emitted by the second light source transmits the second line polaroid and enters a second inlet of the first polarization splitter, and emergent light of the first polarization splitter enters an inlet of the light splitting/light composition optical path system. According to the invention, image contrast of the polarizing type stereo projector can be raised fundamentally.
