This paper investigated the effects of technological innovation capabilities and export activities on growth rates and profitability in mid-sized enterprises. For this purpose, the study analyzed 10-year panel data of mid-sized enterprises identified based on legal criteria. Domestic mid-sized enterprises could be classified by firm size and ownership independence into three types: those that continuously maintained mid-sized enterprise status, those that recently grew from small and medium-sized enterprises (SMEs) to mid-sized enterprises, and those that are affiliates of large-scale corporations. Each type exhibited different internal firm characteristics. This study sought to empirically determine whether the effects of technological innovation and exports on business performance differ across these identified types of mid-sized enterprises. According to the research findings, at the individual mid-sized enterprise level, an increase in technological innovation generally had a positive impact on growth rates and profitability, and this positive effect of technological innovation was found to be relatively amplified or more statistically significant in the type of firms that had grown from SMEs to mid-sized enterprises. Additionally, an increase in export share within mid-sized enterprises generally had a positive impact on the growth rates and profitability of mid-sized enterprises overall. The positive effect of exports on business performance was also amplified in the type of firms that had grown from SMEs to mid-sized enterprises. These findings suggest that SMEs that have strengthened their competitive advantage through accumulating technological innovation capabilities or engaging in active export activities can continue to grow and become mid-sized enterprises.