In this article we develop a method to evaluate the poling quality of optical superlattice (OSL) based on two-dimensional (2D) Fourier transform. To demonstrate this method, -Z or +Z face etched OSL samples with desired patterns are fabricated by standard electric field poling technique. By analyzing the processed micrograph of the etched surfaces, the magnitude of the reciprocal vectors of the OSL are calculated directly and rapidly. Second harmonic generation (SHG) experiment is performed to validate the evaluation result.