Integrated scatterometer for qualification of superpolished substrates for laser-gyro by surface scatter loss measurement is constructed. Different from the qualification of substrate by surface roughness, the scatterometer measures the forward surface scatter loss to check whether the mirror made of the substrate will be suitable for the required laser-gyro lock-in specification. The scatterometer utilizes convex lens instead of integrating sphere to collect scatter light. Special sample support and baffle are designed to block unwanted light. The result of stability test is given, which is about 0.4% over 10 h.