High-optical quality lattice-matched InxGa1-xAs/InxAl1-xAs quantum MTlls (QWs) with indium contents of x = 0.18-0.19 have been successfully grown on (4 1 1)A- and (1 0 0)-oriented InGnAs ternary substrates by molecular beam epitaxy. Strong photoluminescence (PL) with a narrow linewidth was observed from both (4 1 1)A and (1 0 0) QWs at 12 K. The peak energy of PL from QWs had a good correlation with the calculated exciton emission energy based on the band parameter of the InGaAs well layers and InAlAs barrier layers. The result indicates that the (4 1 1)A and (1 0 0) InGaAs/InAlAs QWs on InGaAs ternary substrates have 0.2 eV larger energy gap difference between their well and barrier materials than GaAs/AlAs QWs on GaAs binary substrates or InGaAs/InAlAs QWs on InP binary substrates. In addition, the (4 1 1)A In0.18Ga0.82As/In0.18Al0.82As QWs had a narron cr PL linewidth than (1 0 0) QWs indicating that smoother interfaces were realized in the (4 1 1)A QWs.