In knowledge communities, language style has a significant impact on the perceived satisfaction of knowledge recipients and the depth of knowledge interactions. Although existing studies have focused on the quality and efficiency of knowledge interaction, they have not fully explored the role of language style in online knowledge communities or its impact on knowledge interaction. This study provides new insights into understanding the influencing factors of knowledge interactions in knowledge communities and has important implications for how to optimize language style in knowledge communities and improve the quality of knowledge interactions between knowledge producers and recipients. The theoretical hypotheses were proposed based on language expectation theory and information quality theory. Then, 19,416 knowledge interaction records of 346 knowledge contributors in the knowledge community were obtained, and empirical analysis was conducted using a fixed-effect model. The results show that a professional language style could enhance the depth of knowledge interaction, but might reduce the perceived satisfaction of knowledge recipients. Conversely, a social language style may reduce the depth of knowledge interaction but increase the perceived satisfaction of the knowledge receiver. In addition, the knowledge anxiety level of the knowledge receiver also affects the impact of language style on knowledge interaction and perceived satisfaction.