InGaAsP/GaAs0.7P0.3 stripe geometry DH visible laser diodes having a p-type cap layer are fabricated. The advantage of the use of GaAs0.7P0.3 substrate instead of GaAs0.6P0.4 is discussed in terms of the injected carrier distribution ratio in direct valley (Γ) to X and L valleys. The fabricated diodes operate at room temperature under pulsed-condition. Minimum threshold current density is 4.5 kA/cm2 at a lasing wavelength of 663.0 nm.