3 5 ABSTRACTAn objective of the present invention is to provide stable antibody-containing 5 formulations which are suitable for subcutaneous administration and in which aggregation formation is suppressed during long-term storage.The present inventors discovered that a significant stabilization effect was achieved by using an acidic amino acid, aspartic acid or glutamic acid as a counter ion species in histidine buffer or tris(hydroxymethyBaminomethane, specifically by using histidine-aspartate buffer or 10 histidine-glutamate buffer, or tris(hydroxymethyDaminomethane-aspartate or tris(hydroxymethyBaminomethane-glutamate as a buffer. The present inventors also discovered that a significant stabilization effect was achieved by using an acidic amino acid, aspartic acid or glutamic acid, as a counter ion species to a basic amino acid such as arginine, specifically by using arginine-aspartate or arginine-glutamate.