Abstract Oman is a Middle Eastern country that has traditionally been monotonically reliant on its indigenous fossil fuel supplies. Besides, the nation has also been a surplus producer and net exporter of oil which further highlights the prolonged fossil fuel dependency of Oman. Consequently, despite fourishing economically, environmental quality in Oman has persistently aggravated. These opposing economic and environmental performances have necessitated Oman to identify the factors which can enable Oman to decarbonize its economy for tackling the environmental concerns faced by the nation. Against this backdrop, this study aims to examine the symmetric and asymmetric efects of foreign direct investments, economic growth, and capital investments on carbon dioxide emissions in Oman during 1980–2019. Using relevant econometric estimation methods for controlling structural break concerns in the data, the fndings reveal evidence of asymmetric environmental impacts associated with shocks to the nation’s foreign direct investment infow, economic growth, and capital investment fgures. Specifcally, it is witnessed that positive shocks to the levels of foreign direct investment infows, economic growth, and capital investments boost carbon dioxide emissions both in the short and long run. On the other hand, negative shocks to the levels of foreign direct investment infows and economic growth are witnessed to reduce the emissions. Besides, the fndings also validate the environmental Kuznets curve and pollution haven hypotheses in the context of Oman. Hence, considering these key fndings, it is recommended that Oman should ideally pursues green economic growth policies by restricting infows of unclean foreign direct investments and green its fnancial sector in order to collectively minimize its carbon dioxide emission fgures.