The present invention provides liquid formulations of SYNAGIS.RTM. or an antigen-binding fragment thereof that immunospecifically bind to a respiratory syncytial virus (RSV) antigen, which formulations exhibit stability, low to undetectable levels of aggregation, and very little to no loss of the biological activities of SYNAGIS.RTM. or an antigen-binding fragment thereof, even during long periods of storage. In particular, the present invention provides liquid formulations of SYNAGIS.RTM. or an antigen-binding fragment thereof which immunospecifically binds to a RSV antigen, which formulations are substantially free of surfactant, inorganic salts, and/or other common excipients. Furthermore, the invention provides method of preventing, treating or ameliorating symptoms associated with RSV infection utilizing liquid formulations of the present invention.