Quasi-phase-matching is a technique for phase matching nonlinear optical interactions which the nonlinear coefficient is modulated spatially at regular intervals using a structural periodically built into the nonlinear medium. Using this technique, higher conversion efficiency can be obtained and nonlinear interactions over the entire transmission band of the material can be utilized. In particular, the periodically poled domain structure in LiNbO3 has become the most important sample, which was fabricated by domain engineering. The development and trend of quasi-phase-matching technique are introduced in detail.