Abstract : We present the first demonstration of waveguide-type depleted optical thyristor laser diode with InGaAs/InGaAsP multiple quantum well structure. The measured switching voltage and current are 4.63 V and 10uA respectively. The holding voltage and current are respectively 0.59 V, 20uA. The lasing threshold current at the temperature of 25 ∘ C and 10 ∘ C are 111 mAA and 72.5 mA, respectively. The lasing wavelength is centered at 1.561um at a bias current equal to 1.41 times threshold.