Objective The measurement error is fairly great in blood cell analyzer at present. To reduce the error, the curve fitting model based on Matlab is supposed to be applied. Methods The errors of the platelet count in measurement and Coulter theory were corrected with the method of curve fitting in this paper. Results The two examples with curve fitting method were completed and their results indicated that curve fitting based on Matlab was feasible and valid for correcting the errors from measurements. Conclusions Curve fitting based on Matlab is useful to correct the measurement error of blood cells.