The invention discloses a multi-symbol joint channel estimation method in high speed mobile environment, wherein the method is based on an OFDM wireless communication system, and a channel estimation method based on pilot frequency is used. The multi-symbol joint channel estimation method in high speed mobile environment comprises the following steps of: 1) modelling for a time frequency double selective channel through a complex exponential-basis expansion model; 2) calculating the number J of joint estimation OFDM symbols, meeting that the channel corresponding to J continuous OFDM symbols has joint sparse property; 3) for the J continuous OFDM symbols, designing a sparse pilot frequency mode, and deriving a channel estimation model; 4) obtaining optimal pilot frequency position distribution through a discrete random optimization algorithm; 5) reconstructing a sparse coefficient through a block synchronization orthogonal matching pursuit (BSOMP); 6) recovering a channel tapping coefficient according to a coefficient reconstructed by a BSOMP algorithm; 7) performing piecewise linear smoothing for the channel tapping coefficient obtained through estimation. The multi-symbol joint channel estimation method in high speed mobile environment can effectively resist time frequency double selective fading, and can improve channel estimation accuracy and spectrum efficiency.