The innovation behavior of small and medium-sized enterprises (SMEs) is raising more and more questions, not only regarding their performance and competitive position but also affecting their economic perception. It is well known that SMEs are key players in the economy, which also holds true for the Hungarian economy. This research focused on examining the factors influencing the innovation activities of SMEs operating in the Hungarian construction industry. The empirical research was conducted using a questionnaire survey. A total of N=169 construction companies were surveyed. The validity of the hypothesis formulated in the research was tested using parametric ANOVA analysis. The main finding of the study is that significant differences can be identified in innovation activity based on company size among SMEs operating in the construction industry. The most intense innovation gap exists between medium-sized enterprises and micro and small enterprises, influenced by the innovation behavior of competitors, the demand for new management innovations from industry associations, the lack of technological preparedness within the company, and the innovation willingness of the management. For SMEs in the construction industry, staying up to date and allocating more resources to developing their innovation behavior is crucial for their operation and market presence. Within the industry, the key to success lies not only in surpassing competitors and convincing management but also in prioritizing technological innovations.