The topic of the current diploma thesis is the optimisation of the mixing time of dry mortar products. In the forefront of the investigations it was necessary to find an appropriate parameter for the evaluation of the test results in order to determine the optimal mixing time. On the basis of mixing tests and the relevant evaluations ways to a both economically and qualitatively optimal homogeneity could be found. Besides the identification of the optimal mixing time, relevant questions regarding the technical process which shall determine the future flow chart of mixing in the plant could be answered. Furthermore, optimal dosage sequence and the place of posting of the components could be found. In the course of the mixing tests a documentation of the mixing amount, the filling degree of the mixture and the energy consumption of the mixer took place as well. From the results it could be derived that these factors were set up optimally already. Summarizing the results of the extensive investigations it can be stated that the mixing times suggested by the mixer manufacturers are not optimised except for one examined product. A reduction of the mixing time resulted in a better homogeneity for three of the four examined products and furthermore in a reduction in production time and energy.