Lateral confinement of the current is significant to semiconductor lasers. Lateral confinement can be achieved and threshold current density can be decreased in certain range if lateral confinement structure is embedded in active region of semiconductor lasers. But conventional lateral confinement method cannot suppress the lateral spread current effectively no matter whether lateral waveguide structure or shallow isolation groove is adopted. A new type of deep isolation groove structure is proposed, and lateral confinement is stimulated based on Comsol software. The deep isolation groove structure with etching depth more than the thickness of epitaxial layer is more effective when enhancing current injection efficiency. Two deep isolation grooves of 4 μm depth located at 100 μm away from the ridge type at both sides are etched by inductively coupled plasma etching. Experimental results show that, given the current of 5 A, the output power of semiconductor laser chip with cavity length of 4 mm and deep isolation groove is 3.6 W. The threshold current is 0.3 A. The threshold current density is 78.95 A/cm2. It indicates that the new type of deep isolation groove structure can suppress the lateral spread of the current effectively.