A scheme for laser jamming using quasi parallel light interference was proposed. On the basis of the interference theoretical analysis, the multi-beam quasi parallel light interference images and interference intensity maximum value of two beams, three beams and four beams were obtained by He-Ne laser, and the interference images and the light intensity distribution were got by simulation. Both theoretical and experimental results show that the patterns of quasi parallel light interference images depend on beam direction angle. In certain direction angle, there is bright stripes or bright spots of interference in the middle of the interference field. The distance between interference stripes or spots is decided by the angle between two beams of light. When the value of the angle between two beams is no more than 0.5 mrad, the experiment data is consistent with the simulation data, and the interference intensity maximum is close to the result of theoretical maximum, that is the light intensity maximum of two, three and four beams of quasi parallel light interference are four, eight, fifteen times the size of the light intensity of single beam. The effect evaluation and the test of validity of laser jamming scheme were given.