Abstract: Taking the alkalimetric determination of citric acid as an illustration, the basic principle, operation procedure and data treatment related to application of combinatorial measurement and regression analysis to precision titrimetry were introduced systematically. Besides, details related to the standardization of NaOH standard solution were also presented. A brief description of the application of the above mentioned chemometric algorithm to other titrimetric methods, including coordination titrimetry, redox titrimetry and precipitation titrimetry, was also given. As shown by the results obtained, although no significant difference was observed between the results of the present method and the conventional method, but raise of precision and reliability of the results of the present method was obvious, and in addition, measurements with zero deviation at millionth or 1/10 millionth digits were attainable.