To solve the problem of shrinkage voids in carbon fiber reinforced polymer (CFRP)/steel dissimilar joint，the fiber laser surfi-sculpt on the GMW2 autobody sheet steel is adopted. The effects of laser power, scanning speed, scanning length and scanning repeats on the width and height of protrusion are systematically investigated. The laser surfi-sculpt process is studied by high speed visual detection system. The results show that the protrusion width is the same as the molten pool width. Increasing the laser power or decreasing the scanning speed will cause the increase of molten pool width, leading the protrusion width to increase. While scanning length and scanning repeats do not affect the molten pool width, so they have no effect on protrusion width. The protrusion height is determined by vaporization pressure, surface tension and hydrodynamic pressure. With the laser power increasing, the vaporization pressure increases and the surface tension decreases. Namely the driving force for the liquid metal flow to the behind of molten pool increases. So the appropriate increase of laser power is beneficial for protrusion to grow taller. When the laser power is too high, a large number of spatters will be produced, leading to the protrusion height instable. With the increase of scanning speed, vaporization pressure, surface tension and hydrodynamic pressure will change. There is a competition between driving force and resistance, which leads the protrusion height first to increase and then decrease. With the increase of scanning length, the horizontal component of vaporization pressure and the driving force increase, leading to the increase of protrusion height.