The role of environmental tax as an economic instrument to reduce environmental degradation has been under investigation for many years. In this paper, the main research objective is to check whether there were long-term relationships (cointegration) between greenhouse gas emissions, environmental taxes and gross domestic product in Visegrad Group countries under the inverted U-shaped Environmental Kuznets Curve (EKC) hypothesis from 1995 to 2018. It was also checked whether environmental tax has an impact on greenhouse gas emissions. In the first step, the long-run relationship (cointegration) was examined by applying the Autoregressive Distributed Lag (ARDL) bounds test. In the second step, the causal relationship and direction were tested within the Vector Error Correction Model (VECM) framework. The results of ARDL bounds testing confirmed cointegration between variables only in Poland. However, the long-run relationships between the variables are not consistent with the inverted U-shaped EKC hypothesis. They confirm the U-shaped EKC hypothesis, indicating that greenhouse gas emissions decrease with an increase in GDP per capita. After reaching the minimum, emissions increase again. The test of the causal relationship in Poland indicates the existence of convergence to the long-term equilibrium only for the equation where the environmental tax is the dependent variable.