Using data of wind speed, air temperature and humidity recorded simultaneously on board and the on the small buoy, the latter is considered as criterion, the paper has discussed the influence of the body of ship on the meteorological data. Owing to the disturbance and the influence of heat radiation from the body of ship, the temperature observed on board is higher by about 2癈 than on buoy, and the relative humidity lower by 10%, wind speed observed on the mast is not only irregular but is less than that on the buoy, the error of which would be 3 m/s. The paper therefore suggests that the data observed on the deck in daytime, especially in fair weather after midday, is less reliable. The reliability of data decreases simultaneously with the increase of the body of ship in size.In addition, this paper also proposes that more reasonable observing points chosen on board should be the key to obtain reliable data. By analysis, it is believed that the meteorological data observed on ship’s bow or upwind outs Using data of wind speed, air temperature and humidity recorded simultaneously on board and the on the small buoy, the latter is considered as criterion, the paper has discussed the influence of the body of ship on the meteorological data. Owing to the disturbance and the influence of heat radiation from the body of ship, the temperature observed on board is higher by about 2 癈 than on buoy, and the relative humidity lower by 10%, wind speed observed on the mast is not only irregular but is less than that on the buoy, the error of which would be 3 m / s. The paper causes suggests that the data was on the deck in daytime, especially in fair weather after midday, is less reliable. The reliability of data decreases simultaneously with the increase of the body of ship in size. In addition, this paper also proposes that more reasonable observing points chosen on board should be the key to obtain reliable data. By analysis, it is believed that the meteorological data observed on ship’s bow or upwind outs