The transcription factor, GATA-1, plays an important role in the FcεRI α chain expression in mast cells and basophils. This study was conducted to investigate the downregulation of the transcription factor GATA-1 by kaempferol isolated from Nelumbo nucifera stamens in FcεRI-mediated allergic reactions. Kaempferol inhibited FcεRI-mediated histamine release. Western blotting analysis and RT-PCR showed that the protein and mRNA expression of GATA-1 was suppressed by kaempferol in a dose-dependent manner. These results suggest that kaempferol may inactivate basophils by downregulating the FcεRI α chain expression via the inhibition of the GATA-1 expression.