It has long been a difficult task to use old methods to estimate rapidly and synoptically the primary productivity of sea waters. The satellite remote sensing data has been used to analyse the chlorophyll-a content in the Huang Hai and Bo Hai Seas in this paper. It demonstrates tb.at the correlation between the satellite-derived cont-ent and the measured content of the both seas in the same month seems very. close,i. e.，the distribution pattern of chlorophyll-a agree with the accumulated knowledge from the productive practice for many years. Hence, the originally processed--image has been rectified by the geometric deformation, a symbolic chart for interpretating the chiorophyll--a content distribution is obtained. Eased on the above work, the values for primary productivity in the euphotic layer of 23 waters in Huang Hai and Bo Hai Seas are calculated by using the empirical formula. It is obvious that this work should he considered important not only to science, but also in directing the fisheries and mariculture.