Gaseous phosphine (PH 3 ) in the inshore atmosphere was observed from October 2005 to August 2006 at a coastal site of the Yellow Sea in China. The concentration of PH 3 ranged from 0.01 to 14.86 ng m −3 with an average of 1.14 ng m −3 . The concentration showed a diurnal variation in PH 3 with the peak occurring at morning and the lowest point at noon. An obvious seasonal variation of atmospheric PH 3 was found, with the PH 3 levels in the summer higher than those in the winter. The PH 3 levels in the atmosphere were apparently affected by temperature, radiation, sources, and other meteorological factors. The data indicate that PH 3 can be transported between the terrestrial and inshore atmosphere of Qingdao and the Yellow Sea or the East China Sea in both directions. The study increases evidence that PH 3 participates within the global biogeochemical phosphorus cycle in P transport from land and inshore waters to the sea where commonly P is scarce and where PH 3 inflow could be of important.