The effect of hydrogen (H) plasma passivation on a vertical-cavity surface-emitting laser (VCSEL) structure consisting of an active layer of Al0.3Ga0.7As/GaAs multi-quantum-well (MQW) grown on an Si substrate is investigated by photoluminescence (PL) measurement. Significant spontaneous emission enhancement is observed at the cavity mode for the H-plasma-passivated sample. This is attributed to the increased MQW PL emission resulting from the incorporation of hydrogen atoms which passivated the electrical activity of the defects-related nonradiative deep centres and increased the minority carrier lifetime.