The invention provides a 
signal-to-
noise-ratio 
estimation method which is used for estimating the 
signal to 
noise ratio of a receiving 
signal according to 
pilot frequencies inserted into the receiving signal. The signal-to-
noise-ratio 
estimation method includes the following steps: S1, a 
pilot frequency numerical value Xm, k, a channel 
estimation value Hm, k and 
Gaussian white noise Nm, k of the positions where the 
pilot frequencies are located are obtained from the receiving signal, wherein the m and the k show that the corresponding pilot frequencies are located at the mth data symbol and the kth 
subcarrier; S2, pilot frequency position information Ym, k of the positions where the corresponding pilot frequencies are located is obtained according to the pilot frequency numerical value Xm, k, the channel estimation value Hm, k and the 
Gaussian white noise Nm, k; S3, a signal-to-noise-ratio estimation value of the receiving signal is obtained according to the pilot frequency numerical value Xm, k, the channel estimation value Hm, k and the pilot frequency position information Ym, k. By means of the signal-to-noise-ratio estimation method, under the condition that the number of the pilot frequencies inserted into data symbols is limited and a large amount of statistics cannot be carried out, contiguous items between the noise and the signal can be eliminated, the accuracy and the stability of the 
algorithm estimation value can be optimized, and the computing complexity can be simplified.