A method and a device for ranking frequencies are provided. The method includes: acquiring the strongest m frequencies in the neighboring cells as alternative frequencies, wherein m is greater than 1; after a preset period, acquiring all the n frequencies in the current neighboring cells; acquiring a frequency with the weakest signal from the alternative frequencies as the weakest frequency; selecting any one frequency X in the n frequencies except m frequencies; comparing the frequency X with the weakest frequency, and replacing the weakest frequency with the frequency X to update the alternative frequency if a signal of the frequency X is stronger than a signal of the weakest frequency; judging whether all of the n frequencies except m frequencies are selected, if no, repeating the steps above, and if yes, outputting the alternative frequencies; ranking the alternative frequencies according to the signal intensity.