After the research we can conclude that most scientists use the term synchronization to explain the coherence between the cyclical growths between countries. The variables such as GDP, consumption and investment are rising/falling/changing over time because the statistical measurements of business cycles require time series. This specific problem is resolved by the extraction of trend, or de-trending data. Such a procedure in macroeconomics is enabled by using the Hodrick Prescott filter that we used in the analysis of business cycles. Methodological framework of this study is based on two analyses: the first is evaluation of cyclical characteristics of macroeconomic variables and the second is measuring of synchronization of business cycles of Slovenian economy with the EU average. Results of the analysis, as presented, show that the level of synchronization and similarity fluctuate over time, however, synchronization is much less volatile than similarity. The correlation of 0.17% between the two measures over time illustrates that the synchronicity and similarity are in fact two different concepts which tend to change and fluctuate within the time domain. Also, it shows that variations in the business cycles and the effects of different shocks have different effects on the behaviour and the extent of growth in Slovenia, which is indicative for the rational economic policy. After all, the conclusion is that both coherence measurements increase under the analyzed period, or, their positive trend is somewhat different while most of the selected variables show pro-cyclical leading trends. The conclusion is that we cannot talk about the clear separation phase for Slovenia, as long as the development of trade and financial flows affect the greater synchronization of economic growth between Slovenia and the EU, especially after the adoption of the euro, only the previous crises obstruct this pattern in certain aspects. In fact, the concept of synchronization still has time and space to gain a higher level of empirical respect, especially within the countries of Central and Eastern Europe.