The preliminary aim of this study is to explore the intrinsic and extrinsic motivational factors for knowledge sharing in co-working spaces. This study employed a qualitative approach based on in-depth interviews. The key interviewees were management personnel from 19 co-working spaces in Thailand categorised according to the sector. The motivational factors can be divided into two categories: intrinsic and extrinsic. Intrinsic motivation consists of four sub-categories: altruism, knowledge self-efficacy, self-interest, and job autonomy. Extrinsic motivation consists of five sub-categories: reward, reputation, networking, environment, and reciprocity. The findings of this study demonstrate that motivational factors support knowledge sharing in co-working spaces. The results further reveal that networking is the most significant motivational factor. Interviewees from the private sector revealed that intrinsic motivational factors were more effective than extrinsic. On the other hand, representatives from both the public and higher education sectors suggested that extrinsic motivational factors were more effective than intrinsic.