As a wave breaking model in the Boussinesq equation, The quasi-bore model was developed by Hara and Hirayama et al.(2003). This model assumes that the energy loss due to hydraulic jump bore in the short space and at a short time becomes the same to the wave energy loss in wave breaking during one unit of time. Since original of the quasi-bore model was a one-dimensional section model, some extension is necessary to apply it to the two-dimensional plane wave breaking model. 　The paper studied on the applicability of the one-dimensional quasi-bore model in the two-dimensional wave transformation model in the Boussinesq equation. The wave breaking computation term was not modified and directly employed in the Boussinesq equation trems. 　In the paper, the wave breaking transformation on uniform slope was discussed at the first. The wave height gap from the results derived from the former wave breaking model was expressed. Secondary,the wave transformation on circular reefs and around offshore breakwaters were demonstrated and compared with the experimented results. 　The wave height computed in the one-dimensional quasi-bore model agreed well with the experimental wave height in the studied model. The wave direction becomes almost normal to the depth contours, and wave directionality is small. However, when wave breaks in the ocean of themulti-directional irregular waves, application of the quasi-bore model was not perfect.