Embodiments of the present invention provide an optimizing apparatus and method for a pulse shaping filter and a transmitter. The apparatus is configured to determine an initial peak-to-average power ratio threshold of the pulse shaping filter, and determine an initial filter coefficient of the pulse shaping filter according to the initial peak-to-average power ratio threshold; determine a constraint condition for optimizing the pulse shaping filter according to the initial peak-to-average power ratio threshold and the initial filter coefficient of the pulse shaping filter; wherein the constraint condition comprises a threshold constraint in a filter coefficient sign domain; and adjust the initial peak-to-average power ratio threshold and the initial filter coefficient of the pulse shaping filter in a case where the constraint condition is satisfied, until a predefined condition is satisfied, so as to obtain an optimized filter coefficient of the pulse shaping filter.