This paper reports a qualitative study investigating the viability of instant messenger (IM) interaction to facilitate intercultural learning in a foreign language class. Eight students in a Chinese as a foreign language (CFL) class participated in the study. Each student was paired with a native speaker (NS) of Chinese, and each pair collaborated on eight intercultural-learning tasks over a 2-month period through IM. Data were collected through an ethnographic survey, intercultural sensitivity scale, follow-up interviews, the researcher's reflective journal, and participants' IM conversation transcripts. The results showed that student participants' intercultural interaction engagement and attentiveness steadily increased, they developed self-reflection capacities, critical thinking skills, and greater sensitivity and respect for intercultural differences during their IM-based intercultural learning. Participants also had predominantly positive attitudes toward IM use in intercultural learning.