While 'open innovation' is often considered to be an organisational strategy with universal application, its generalisability and applicability to organisations operating within emerging economies has yet to be fully explored. This study provides empirical evidence of its importance within a substantial sample of Chinese large firms and small and medium enterprises. Using Tobit regression analysis, our findings indicate that external knowledge sources from inter-firm networking are more important in creating the benefits of open innovation for Chinese small and medium enterprises than their larger peers. Linkages to university and research institutes generally have few direct effects on the innovation performance of both large and small firms in China. However, the role of universities and research institutes is shown to be important among our large firm sample when combined with evident internal absorptive capacity. This interaction is generally limited to our large firm sample, and is not as evident among small firms.