Abstract: In this paper, atmospheric stratification in the boundary layer for warm pools of the tropical West Pacific are analyzed using the hydrographical, meteorological and low-level atmospheric observations from the 4th cruise of PRC-USA Joint Air-sea Interactions Studies in this part of the o-cean. It is pointed out that the stratification is characterized by multiple temperature inversion layers in spring and there are 4 such layers in most cases, with the usual thickness over 30 m, the largest reaching 336 m. The findings are important addition to the work on the structure of the boundary layer over tropical oceans.