The optical characteristics of tunnel－junction－regenerated multiple active regions intracavity－contacted Vertical Cavity Surface Emitting Laser (VCSEL) have been investigated. By the longitudinal optical standing wave field simulated, the standingwave effect is analyzed. The gain peak wavelength,the resonance cavitywavelength,the centerwavelength of Distributed Bragg Reflector (DBR) and the thickness deviation ofVCSEL are obtained. The reason why the device could not lase is also analyzed and exp lained using the gain spectrun. Moreover, the edge－emission mode characteristics of intracavity－contacted VCSEL is obtained by simulative calculation.The numerical result show sthat the optical field distribution is very different from that of Edge－Emitting Laser due to the DBR structure, and the simulated result of the far field angle is closely accorded with the measured result.