This paper examines the effect of trade liberalization or globalization, more broadly, on plants’ growth as well as on “bi-polarization”. To do so, we reviewed the possible theoretical mechanisms put forward by recent heterogeneous firm trade theories, and provided available micro-evidence from existing empirical studies on Korean manufacturing sector. Above all, the empirical evidence provided in this paper strongly suggests that globalization promoted growth of Korean manufacturing plants. Specifically, evidence suggests that exporting not only increases within-plant productivity but also promotes introduction of new products and dropping of old products. However, the empirical evidence also suggest that globalization has some downsides: widening productivity differences across plants and rising wage inequality between skilled and unskilled workers. Specifically, trade liberalization widens the initial productivity differences among plants through learning from export market participation as well as through interactions between exporting and R&D, both of which increase plants’ productivity. We also show that there is only a small group of large and productive “superstar” plants engaged in both R&D and exporting activity, which can fully utilize the potential benefits from globalization. Finally, we also show evidence that trade liberalization interacts with innovation to increase the skilled-unskilled wage inequality.