1977–78 United States network television schedule (late night)

The 1977–78 United States network television schedule (late night) details the programming aired by the three major broadcast television networks—ABC, CBS, and NBC—during the late-night time slots (typically defined as after 11:00 PM Eastern/Pacific). This schedule lists the specific shows broadcast during this period, offering a snapshot of late-night television programming at that time. This era was characterized by talk shows, variety programs, and reruns of earlier primetime series. Key programs would have included The Tonight Show Starring Johnny Carson on NBC, various late-night movies on CBS, and ABC's late-night offerings, which may have included a mix of news, talk, and entertainment shows. The schedules would differ slightly depending on the individual affiliate stations in each market.