The invention relates to a plasticizer production wastewater total nitrogen testing method. The method comprises the following steps of 1, sucking waste liquid by using a transfer pipette or weighingwaste residues, and putting the waste liquid or the waste residues into a distillation flask filled with distilled water, 2, connecting the distillation flask with a distillation device, enabling thedistillation device to be connected with a beaker through a condensation pipe, containing sulfuric acid liquid in the beaker, and enabling a glass tube at the tail end of the condenser tube to be inserted into the sulfuric acid liquid, 3, adding a sodium hydroxide solution into the distillation flask, and carrying out heating distillation on the distillation flask until two thirds of the solutionin the distillation flask is evaporated, washing the condenser pipe with distilled water, and introducing the washing liquid after washing into the beaker, 4, adding a methyl red methylene blue mixedindicator into the beaker, and titrating the residual sulfuric acid solution in the beaker by using a sodium hydroxide solution until the sulfuric acid solution is changed into grey green from red purple, and 5, calculating the total nitrogen content. Compared with the prior art, the plasticizer production wastewater total nitrogen testing method is simple, is not influenced by COD in the wastewater and metal ion interference, and is high in repeatability and accuracy, and has a wide application range.