The present invention provides liquid formulations of antibodies or antibody fragments that immunospecifically bind to an IL-9 polypeptide, which formulations exhibit stability, low to undetectable levels of aggregation, and very little to no loss of the biological activities of the antibodies or antibody fragments, even during long periods of storage. In particular, the present invention provides liquid formulations of antibodies or fragments thereof that immunospecifically bind to an IL-9 polypeptide, which formulations are substantially free of surfactants, sugars, sugar alcohols, amino acids other than histidine (preferably with pKa values of less than 5 and above 7), and / or other common excipients. Furthermore, the invention provides methods of preventing, treating or ameliorating a disease or disorder associated with or characterized by aberrant expression and / or activity of an IL-9 polypeptide, a disease or disorder associated with or characterized by aberrant expression and / or activity of the IL-9R or one or more subunits thereof, an autoimmune disease, an inflammatory disease, a proliferative disease, or an infection (preferably, a respiratory infection), or one or more symptoms thereof, utilizing the liquid formulations of the present invention.