A downlink channel estimation method and system, and a mobile terminal. In the method, a first mobile terminal is located in a central area of a cell, a second mobile terminal is located in an edge area of the cell, and a resource block of the second mobile terminal is adjacent to a resource block of the first mobile terminal, so that the first mobile terminal can use a data signal transmitted from a base station to the second mobile terminal to perform downlink channel estimation, thereby improving the accuracy of the downlink channel estimation, and enhancing the performance of the downlink channel estimation.