A bracket assembly for a rack is provided. The rack has a plurality of holes. The bracket assembly includes a bracket having multiple bracket holes, a base securely connected to the bracket, and a fastening member pivotally connected to the bracket. The base includes multiple connection members corresponding to the bracket holes. The fastening member includes a resilient leg and a fastening arm. The fastening arm has at least one fastening portion. One of the connection members is inserted into one of the holes of the rack. The fastening portion of the fastening arm is hooked to the rack so as to connect the bracket to the rack.