In the context of classic Nokia mobile phones (roughly from the late 1990s to the early 2010s), the term "Nokia USB ROM" refers not to a single file or chip, but to a process: using a USB cable to write (or "flash") the phone’s ROM firmware (Read-Only Memory software) directly to the device.

Today, the era of "Nokia USB ROM" is largely obsolete. Modern smartphones (including new Nokia-branded phones from HMD Global) run Android, which is flashed via fastboot or recovery, not raw USB ROM writing. However, among vintage phone enthusiasts, modders, and collectors, the skill of USB flashing old Nokias remains a valuable trick—keeping countless classic devices alive long after official support ended.

Nokia USB ROM was the process of using a USB cable and PC software to rewrite the firmware of a legacy Nokia phone, enabling repair, customization, and debricking.