With growing age there occurs a decline in many cognitive functions, such as attention and long-term memory. It is believed that one of the first functions that begin to decline with age are executive functions. Therefore the aim of this study was to examine whether there's a decline in executive functions with age. Participants of the conducted study were adults without disabilities who were divided into two groups. The first group included younger adults (N=15) and the second group consisted of middle-aged adults and the elderly (N=11). Verbal working memory was assessed with the subtest Memory for Digit Span of the WISC-IV test. The CANTAB Battery Tests were administered to assess spatial working memory, planning, cognitive flexibility and response inhibition. The results of the research show that older adults achieved significantly lower results on the working memory variables. The differences were not significant for other executive functions: planning, cognitive flexibility and inhibition. In conclusion, it can be expected that with aging there is a decline in working memory and inhibition. However, when the speed of processing is excluded from the results of inhibition the differences are not found on this variable, which was confirmed with this study. While other researches consistently showed that there is a decline in planning with growing age, contradictory results were found with this study showing no differences. Because some of the declines in executive functions can be seen even in middle-aged adults, this study emphasizes the importance of further researches of executive functions in particular on middle-aged adults.