This paper explains how sociocultural theory (SCT), particularly its three key concepts: mediation, zone of proximal development, and agency, can be used to guide the course design of college-level 1st-year Mandarin Chinese hybrid courses. Specific examples are illustrated to demonstrate how three aspects of the hybrid course design: 1) learning materials and tasks, 2) teacher-student and student-student interaction, and 3) assessments, are guided from a SCT perspective. The feedback from students enrolled in a college-level hybrid Mandarin Chinese course sequence is also provided.