Optical resonance modes have been observed in optically pumped microdisk cavities fabricated from 80 Angstrom /50 Angstrom InGaAs/InGaAsP multiple quantum wells structures grown by gas-source molecular beam epitaxy. We have achieved optically pumped InGaAs/InGaAsP multiquantum Wells microdisk lasers at a pump power threshold of P-th = 150 muW at pump wavelength lambda = 514.5 nm, which was measured for a 10 mum-diameter disk with lasing emission wavelength near lambda = 1.6 mum.