This study focused on trade liberalization and manufacturing sector output of the Nigerian economy. Based on the analytical results it was concluded that while trade openness proxied by trade intensity index increases marginally but fluctuates between the period of 1981 and 2020, the manufacturing sector output increase progressively. Thus, it was concluded that a direct relationship exist between Nigeria trade liberalization policy and the output of the manufacturing sector industrial sector output. Therefore, to check the scourge of escalating negative net export, trade imbalance, and low export of finished goods, there is the need for fundamental changes in Nigeria’s economic structures, especially in its production and consumption patterns. And to do this requires innovative and courageous policy measures. Palliative measures, where necessary should be put in place to cushion the impact of economic openness aggregates on the performance of the Nigerian economy vis-à-vis the manufacturing sectors output.