A method for estimating a signal-to-noise ratio of a received digital radio signal. The estimating method includes a detecting step consisting in recovering a received synchronization symbol contained in the received digital radio signal, and an estimating step configured to determine the signal-to-noise ratio of the received digital radio signal, depending on the difference between a first received synchronization signal and a second received synchronization signal. The first and second received synchronization signals are comprised in the received synchronization symbol.