We report optical properties of the micro-facetted InGaAs quantum wells and quantum wires on non-planar substrates employing magnetophotoluminescence (MPL). The InGaAs/GaAs structures were grown by chemical beam epitaxy on V-groove patterned GaAs substrates. In the presence of a magnetic field of 18 T, the diamagnetic shifts of exciton ground states of the (001)-and side-QWLs are ΔE=15.6 and 10.3 meV, respectively. In MPL of the facetted microstructure, we found that the different diamagnetic shifts strongly depend on the magnitude of the effective magnetic field as well as the quantum confinement. From comparing the intensities and full widths at half maximum, we easily found that side-QWLs are of higher quality than (OOl)-QWLs. We also fabricated InGaAs/GaAs quantum wires with a size of about 200 Å × (500–600) Å. By fitting the diamagnetic shifts (ΔΕ = 9.5 meV) of the exciton ground state with the calculated results of a variational method, we estimated that the reduced mass of the exciton is approximately 0.052 me.