In this study, some certain sizes of triangular, square and circular shaped parts have been cut through CO2 laser cutting centre over a 4 and 6 mm thickness of AISI 304 stainless steel material at different cutting conditions and the effects of cutting parameters were investigated on the dimensional accuracy of the samples. As the independent variables, laser power (W), cutting feed rate (F), focus point (ON) and gas pressure (P) have been selected. By using Full Factorial Experimental Design Technique (TFT), a total of 486 experiments have been carried out on the 4 and 6 mm thick sheet materials at three different levels of the independent parameters. Using the experimental data obtained as a result of the measurements made with three-dimensional coordinate measurement machine (CMM), the second-order predictive models, including the effects of laser cutting parameters on the dimensional accuracy of the triangular, square and circular-shaped samples have been improved through the Regression Analysis. Correlation coefficients of the predictive equations developed in the 95% confidence level have been obtained over R-2=0,78. In this study, furthermore, the main effect graphics showing the effects of independent variables on the dimensional accuracy have also been formed and the effects of parameters were evaluated. The most effective parameters on the dimensional accuracy of the cut parts were laser power, cutting feed rate and focus point, respectively.