We extracted significant wave height (SWH) using several altimeter missions from 1987-1995 over the Northwest Pacific ocean and compared with ECMWF (European Center for Medium- Range Forecast) reanalysis (ERA) products. For large wave heights the ERA wave heights are smaller than the altimetric ones, while for small wave heights the ERA wave heights are larger Comparison in SWH between altimetric derivations and ERA model products shows the discrepancy of 0.46-0.21$ imes$SWH (m). Methods for propagating this differences into ERA wind error are presented.