Although collaborative writing (CW) has become a common pedagogical practice in L2 classrooms, very few studies on CW have been conducted in the context of Chinese as a foreign language (CFL). This study examined students’ perceptional and motivational changes during a 10-week CW project implemented in an intermediate CFL classroom. Data were triangulated from different sources including pre- and post-surveys on students’ beliefs about CW, students’ self-assessment of collaborative performance, and their reflective journals. The study found that students’ perceptions of peer collaboration and personal collaborative behaviors remained stable through the progress of the CW project. However, their feelings towards the CW project revealed fluctuations insofar as they initially felt very positive and motivated to participate but became demotivated as the project progressed due to various factors such as time constraints, group incongruity, and linguistic challenges. They became re-motivated through a growing awareness of satisfying collaborative outcomes and gained a strong sense of achievement. They indicated that they were more confident and prepared to participate in future CW activities. Based on the findings of this study, pedagogical implications are addressed and suggestions are offered for implementing CW in CFL writing classrooms.