Embodiments of the present invention provide a method for processing firmware based on a firmware over the air technology, an apparatus, and a system. The method includes: performing check processing on at least one firmware upgrade file to form first check data; performing encryption processing on the first check data to form first encryption data; and combining the first encryption data, the first check data, and the firmware upgrade file to a firmware upgrade package, and sending the firmware upgrade package through an air interface to a mobile terminal. The apparatus includes: a checking module, an encrypting module, and a processing module. The system includes: a server and a mobile terminal. The embodiments of the present invention, by performing check, encryption, and combination processing on the firmware upgrade file, quickly implements upgrade of multiple pieces of firmware, and improves security of the mobile terminal.