Purpose: With increasing digitalization, the debate on the direction of transformation in various sectors of the economy and their ability to keep up with the changes in this area is becoming increasingly complex. The energy industry is one of the key sectors in the economy, and as such it must follow trends and adapt to changing conditions. The aim of the paper is to diagnose and assess the level of progress in digital transformation among Polish energy sector enterprises. Design/methodology/approach: The research was conducted on a group of 110 entities, with a survey questionnaire. The gathered data was analyzed using descriptive statistics. Findings: Although the level of employing Industry 4.0 tools in Polish energy sector enterprises is at a low level, managers recognize the importance of following the path toward digital transformation. The awareness of particular digital transformation prerequisites differs depending on the phase of the digital transformation process. Research limitations/implications: Among the limitations of the research procedure, issues such as the single respondent design and the exclusion of micro entities from the research should be noted. However, the exclusion of micro entities from the analysis was intentional, and this area deserves the attention of researchers. The specificity of the functioning and organization of the activity of micro enterprises may distort the image of the sector. Referring to the single respondent design, it was assumed that in this phase of the research it is reasonable to collect individual opinions specific to a given enterprise. It would be worth extending the analysis by conducting in-depth interviews or attempting more in-depth research at the level of individual entities. Originality/value: This article contributes to the knowledge of the energy sector in Poland in the context of Industry 4.0. Keywords: digital transformation, digital strategy, digital transformation strategy, prerequisites for digital transformation, energy sector companies.