The invention discloses a channel estimation method based on joint training sequence and pilot in an 802.11n multi-antenna OFDM system and relates to the technical field of communication. The method comprises the following steps: firstly, after a receiving end carries out channel demodulation by a FFT, introducing a long training field in the preamble to estimate the channel information of a training sequence, and improving the channel information by using a weighting matrix, wherein the channel information can be directly used as the data channel value in a subcarrier; secondly, subjecting the data to cyclic shift restoration; finally, estimating a pilot channel by a local pilot value and a received signal at the pilot in order to further eliminate the influence of the frequency offset and the phase noise. The method realizes the channel estimation and the recovery operation of the received signal by using the training sequence, the weighting matrix and the pilot value, avoids a characteristic that the training sequence channel estimation error is large, realizes the combination of the training sequence, the weighting matrix and the pilot distribution, reduces the channel estimation error, and provides a simple and efficient solution for the reception of 802.11n multi-antenna OFDM.