In this article, we report on the growth of 1.3-mum-compressive-strain GaInAsP/InP multiple-quantum-well laser diodes (CS-MQW LDs) with a tensile-strain GaInP quantum barrier (GaInP-QB) in the separate-confinement-heterostructure (SCH) regions. Observed via the photoluminescence (PL) spectra, the optimum Ga composition of GaxIn1-xP-QB, GaInP-QB thickness, and pair number of the GaxIn1-xP-QB are 0.09, 5 nm thick and one pair, respectively. The optimum GaInP-QB structure in the p-side SCH region exhibits the narrowest PL full width at half maximum of 43.1 meV, the lowest threshold current of 23 mA, and the highest characteristic temperature of 52 K for the as-cleaved LDs with a 600-mum-cavity length and a 3.5-mum-wide ridge stripe. This low threshold current is better than that of the LDs with GaInP-QB in the n-side SCH region and that of the conventional LDs without GaInP-QB. (C) 2004 American Vacuum Society.