We studied the growth of InGaAs nanowires on InP(1 1 1)B substrates by selective-area metalorganic vapor-phase epitaxy (SA-MOVPE). We proposed a growth model of InGaAs nanowires based on the observation Of growth under various condition. We investigated the composition of InGaAs nanowires using micro-photoluminescence and confirmed the relation between composition of InGaAs nanowires and the growth rate. (C) 2008 Elsevier B.V. All rights reserved.