N-(fatty acyl) O-aryloxyacetyl ethanolamines, prepared from N-acylethanolamine (NAE) and aryloxyacetic acid, were tested for plant growth regulating activity. Compared with N-stearoylethanolamine, most compounds exhibit improved plant growth stimulating activity. In particular, those with chlorine on aryl ring show better activity than 2,4-dichlorophenyloxyacetic acid in stimulating hypocotyls elongation of rape which indicates that chlorine on aryl ring appears significant. Moreover, these derivatives display improved solubility.