Abstract: In this paper, a wide range of equipment such as particle size spectrometer and automatic weather station are used to measure atmospheric aerosol, atmospheric temperature and humidity during the period of April 10 to 26, 2022 in the Yellow Sea and the East China Sea. The temporal and spatial distribution of aerosol particle number concentration and particle size spectrum and the occurrence of new particle formation (NPF) events in the Yellow Sea and the East China Sea were studied. The results show that the total concentration of Marine aerosol in coastal areas of Jiangsu is 150.79-313.14/cm³ near the land, while the total concentration of Marine aerosol far away from the land is only about 70/cm³; Number concentration spectrum showed a bimodal distribution, and the peak aerosol concentration is higher in the sea area near the land, and there was no significant correlation between temperature, humidity and aerosol concentration; The NPF event formation rate (FR) was 0.14-1.45/(cm³·s), and the growth rate (GR) was about 2.84-17.00 nm/h. Compared with the results of NPF events on land, the concentration of nucleation mode aerosol particle number observed at sea is 1 to 2 orders of magnitude lower, but there is no significant difference between the generation rate and growth rate. It is concluded that the concentration of nuclear mode aerosol and the generation rate of new particles are not the dominant factors in the growth process of new particles. In the study of an NPF event during observation, it is found that compared with the nuclear mode aerosol, the increase of the number concentration of the accumulated mode aerosol is delayed.