The present invention is related to a method and apparatus for setting a power limit for high speed downlink packet access (HSDPA) services. In a wireless communication system comprising a plurality of cells, each cell supports transmissions via at least a dedicated channel (DCH) and a HSDPA channel and is subject to a maximum downlink transmission power limit. In accordance with one embodiment, a radio network controller (RNC) estimates a ratio between the average total downlink transmission power level used by DCHs and the average total downlink transmission power level used by HSDPA services in each cell and sets the maximum HSDPA transmission power limit based on the estimated ratio. In accordance with another embodiment, the RNC estimates an average total power consumed by DCHs in the cell and sets the maximum HSDPA transmission power limit by subtracting the average total power consumed by DCHs from the maximum downlink transmission power level of the cell.