To improve the capillary performance of microgroove suction core, v-shaped scanning method was used to etch non-equal section microgrooves on copper plate. The effects of laser path spacing, scanning speed, scanning times, pulse width, and frequency on the morphology and size of non-equal section microgrooves were studied. It is found that with the increase of laser path spacing, the width of grooves increases, the depth of grooves increases first and then decreases, and the roughness of grooves decreases first and then increases. When the path spacing is between 10 μm and 30 μm, the groove morphology is the best, and the capillary pressure difference between the two ends is large. When the number of laser scanning is 50, the scanning speed is 100 mm/s, the frequency is 40 kHz, the pulse width is 120 ns, and the capillary pressure difference between the two ends of the non-equal section groove etched by nanosecond laser is large. The research can provide reference for improving the heat transfer performance of groove type vapor chamber.