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Intervening government and performing environmental policies are among solutions for reducing production externalities and achieving sustainable development. Indeed, institutional quality is an effective factor in selecting optimal environment policies. This paper tries to identify optimal environmental policy among common public tools for intervening (pollution taxes and permits) in the presence of environmental and economic uncertainties with various institutional quality degrees. In this paper, institutional quality is included in a dynamic stochastic general equilibrium model and its effect on choosing environmental policy is considered. The results showed that pollution permit is preferred to taxation on pollution with various institutional quality degrees. In addition, with improvement in institutional quality, if only shock is an environmental shocks, then taxation on pollution will be an optimal policy.