Novel in situ method to produce quantum dots is reported. Three‐dimensional confinement of carriers to a GaInAs/GaAs quantum well dots is observed by photoluminescence. The confinement potential is induced by stressors, formed by self‐organizing growth of InP nanoscale islands on top barrier GaAs surface. Two transitions arising from the strain‐induced quantum dots produced by two types of InP islands are identified. The luminescence from higher electronic states of the quantum dots having a level splitting of 8 meV is also observed.