In this paper, the comparison of performance degradation between selective emitter (SE) solar cell and traditional homogenous emitter (HE) solar cell under encapsulation and outdoor light exposure was investigated. One cell small module experiments show that the performance degradation under encapsulation is mainly determined by the Jsc (short circuit current density) loss, which is calculated according to the EQE (external quantum efficiency) measurements for detail analyses, and SE one-cell module demonstrates a bigger Jsc loss than HE module does. The 72-cell SE modules present a similar power loss rate as the HE modules after encapsulation. After 360 days' outdoor exposure, SE module demonstrates more power losses compared with HE module; nevertheless, SE PV module still has a larger maximum power than standard HE module.