The firms, that understand the importance of Industry 4.0, which has the potential to change the competitive balances to a large extent, have attempted to shape their strategies within the framework of the new industrial revolution, make investments, and improve their practices. The first thing to do in terms of companies and sectors is the determination of the levels of preparation for this revolution. Only after determining the maturity levels, road maps can be prepared, resources can be allocated to this issue and implemented. This study was carried out in order to have an idea about the Industry 4.0 maturity levels of the companies, In particular, in order to determine the Industry 4.0 maturity levels and weaknesses and strengths of the companies in Sivas. In the study, the maturity model consisting of 6 dimensions, 37 sub-dimensions and 4 evaluation levels named "An Industry 4.0 Readiness Assessment Tool" was used. The application of the model, which was reorganized and turned into a questionnaire, was applied to manufacturing companies in the Sivas organized industrial zone. Descriptive statistics used in the evaluation of the original maturity model were used in the data obtained. The maturity model dimensions and dimensions were evaluated according to the demographic data of the companies and the findings were interpreted. Considering all the dimensions in the maturity model, it was found that the firms participating in the study were at a level below the middle level in terms of Industry 4.0 preparation. It can be said that companies are the most prepared in terms of dimension of Products and Services, and they are the least prepared in terms of dimensions of Production and Operations, Strategy and Organization.