The present disclosure provides an electronic apparatus having an incremental enrollment unit and a method thereof. The electronic apparatus at least includes a microphone, a storage device, and a processor. The storage device stores a first screening rule, an enrollment database, and a first temporary storage library. The processor receives a command voice transmitted by the microphone, and compare the command voice with enrolled voices in the enrollment database. If determining that a similarity is larger than a threshold value, the processor stores the command voice as a first temporarily stored voice in the first temporary storage library. When a quantity of the first temporarily stored voices in the first temporary storage library is larger than a first predetermined value, the processor screens out a part of the first temporarily stored voices according to the first screening rule, so as to perform incremental enrollment.