In this study, the effect of innovativeness of external networks on the corporate innovativeness and innovation performance were explored based on web survey data collected from 230 manufacturing companies. Specifically, according to the manufacturers' business categories divided by the technology level, three groups such as advance technology (electronic/IT), mid- to high technology (automobile/machine), and low technology (textile/clothing) companies were investigated to find out which external network influences corporate innovativeness and innovation performance. In the result, textile/clothing companies were not different in company size, history, and innovation effort from advanced technology and mid- to high technology companies. Collectively, the innovativeness of external networks affected corporate innovativeness and innovation performance. In the result by a business category, innovativeness and innovation performance of textile/clothing companies were affected by the innovativeness of competitors, whereas automobile/machine companies in the mid- to high technology group were affected by suppliers. In addition, advanced technology (electronics/IT) were affected by buyers and competitors. These differences suggest that the way to use vertical networks toward upstream (e.g., suppliers) and downstream (e. g., buyers) as well as horizontal networks toward competitors can be different by the business category of manufacturers. The result would provide implications for the academia and the industry.