Development of printing technology has reached a high level of sophistication with a help of integrated computer systems that give high-quality results on various types of printing substrates. Today a printing substrate is not primarily paper. Namely, although they are not environmentally friendly, plastic materials have excellent physical and mechanical properties and their range of application has increased a lot in everyday life. From the printing industry standpoint, if they are considered data carriers, we can find them in almost every segment of everyday life: colored, printed, personalized, branded, distinctive and in any case - omnipresent. Synthetic printing substrates today are successfully used in production of packaging, highquality printing, ID and travel documents with high level of anti-counterfeiting features. Considering the fact that the number of synthetic prints has increased dramatically, moreover, that there are various types of printing products produced on them, and finally considering the fact that they differ in their characteristics from paper printing substrates there is a reasonable need to define the level of quality of their printing and to define acceptable tolerances in quality. This paper explores the parameters of quality that directly and indirectly influence the quality of the finished product: e.g. the color density, the color difference and all the other parameters that influence the quality of the printing. Measuring shows which values of the above factors can meet the adequate level of quality on synthetic printing substrates it is necessary to give additional attention to the acceptable and non-acceptable tolerances in the course of defining the quality system for production and processes on such printing substrates.