The possibility of simultaneous potentiometric and conductometric titration is considered for determination of the acid (A.N.) and amine (AM.N.) numbers of the amidation reaction mixture for technical fatty acids (F.A.) by diethylenetriamine (DETA). Interpretation of titration curves was performed on the basis of model mixtures for DETA and F.A. industrial sample. The obtained results indicate the possibility of determining A.N. and AM.N. values by sequential titration of one sample for industrial organic products and amidation reaction mixtures.