Oceanic chlorophyll concentration is the important indicator of phytoplankton and water quality. So chlorophyll concentration retrieval is the key factor in ocean ecological system. The paper introduces the bio-optical algorithm of chlorophyll concentration retrieval, in which the algebra and neural networks methods are introduced in model methods. The SeaWiFS data of Chinese sea are processed through the software of SeaDAS, the chlorophyll concentration is retrievable by the SeaWiFS/OC4V4 method, and the results are compared between the real collected chlorophyll concentration and the chlorophyll concentration retrieval.