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.