In paper the ice conditions in the Yellow Sea are estimated on the base of maps of boundaries of ice extending and ice concentration in the period of 1997-2004. The isograms of boundaries of ice extending in the Yellow Sea with probability of 0 %, 25 %, 50 %, 75 % and 100 % were received. The thickness of a fast ice at the end of 1997-2004 winters was calculated by different formulas and satellite maps.