This study investigates the relationship between key process parameters and dimensional accuracy in the fabrication of heat transfer plates for microfluidic heat exchangers using selective laser melting (SLM) technology, addressing issues of high cost and environmental pollution associated with traditional processing methods. Simulation and experimental validation were employed to analyze the effects of scanning distance, laser power, and scanning speed on part accuracy. The findings indicate that scanning distance has a negligible impact on the maximum displacement in the X and Y directions of the fabricated parts, whereas laser power and scanning speed significantly influence dimensional accuracy. Increasing the laser power, the maximum displacement value decreases first and then tends to be stable, since the length of plates in X direction is mainly affected by the edge molten pool, and in the Y direction, the length is mainly affected by the internal molten pool, and the maximum displacement first increases and then decreases. When the scanning speed is increased, the maximum displacement values in the X and Y directions decrease first and then increase. When the scanning distance is 60 m, the laser power is 165 W, and the scanning speed is 1 050 mm/s, plates with good dimensional accuracy can be fabricated.