Use of data on suspended matter in Jiazhou Bay seawater from February 1994 to November 1995, February 1997 to November 1998(16 times investigation) to analyze the horizontal distributions and the seasonal variation of suspended matter showed that the content of suspended matter decreased gradually from the north of the bay to the outside the bay. The highest content of suspended matter was 20 mg/L near the mouth of the Daguhe River, high contents varied from 5 mg/L to 15 mg/L in the middle part of the bay from 3 mg/L to 5 mg/L outside the bay. The seasonal variations of suspended matter were highest in spring, lowest in summer, in-between in autumn and winter. The horizontal distribution of suspended matter was similar to that of particulate organic carbon in the bay. Tide and wave are the main factors affecting the distributions of suspended matter.