Organic pollutants are widespread around our daily life that has brought serious environmental and health issues. Search for an effective technology to completely remove and ideally decompose organic pollutant is the main task for the scientists. There has been growing interest on the photocatalysis for degradation of organic pollutants in recent years, however, the fast recombination between the electrons and holes and the limited absorption in the visible-light range restrict its wide use. Nonlinear optical (NLO) materials with built in electric field are now proved to be a favorable approach for the new candidates and open a new chapter in the photocatalysis field. In this review, we described the fundamentals of NLO materials in the application of the photocatalysis field. The role of the built in electric field improved the charges separation was detailed explained, and next we introduced some classical NLO materials applied in the field of environmental containing the BaTiO3, SrTiO3, and the LiNbO3. In particular, we focused on the recent progress of mixed borate-based polar photocatalyst for the degradation of organic pollutants in our lab. We hope this review will offer a full understanding of borate-based NLO photocatalyst and facilitate the design of new photocatalytic materials for organic pollutant degradation.