A bandwidth adaptation scheme is a scheme that selects a subset of mobile users and adjusts the bandwidth allocated to the mobile users in order to achieve a certain goal. A number of bandwidth adaptation schemes [16]-[21] perform a bandwidth adaptation operation on a single cell. This paper considers a bandwidth adaptation operation may involve multiple cells including a cell and its neighbor cells. Bandwidth adaptation involving multiple cells is not a straightforward generalization of that involving a single cell. The issues that need to be addressed include how to select a subset of mobile users in the overlap areas, how to select a subset of neighbor cells to accommodate the subset of mobile users, and how to adjust the bandwidths of the mobile users in these cells. This paper studies the problem of bandwidth adaptation involving multiple cells. The multi-cell bandwidth adaptation problem has been formulated as a zero-one integer linear programming problem. The multi-cell bandwidth adaptation scheme is obtained by solving the zero-one integer linear programming problem. We show that the multi-cell bandwidth adaptation scheme can effectively increase the revenue and reduce the blocking and the forced termination probability compared with a bandwidth adaptation scheme that involves only a single cell.