A method for compensating the frequency dependent phase imbalance in a transmitter is provided. The transmitter processes a baseband signal. The method includes the following steps: (a) compensating the baseband signal with a predetermined delay amounts; (b) inputting the compensated baseband signal to an upconversion circuit to generate a radio frequency (RF) signal; (c) inputting the RF signal to a delay information extractor to obtain a correlation value related to the information of the predetermined delay amount; (d) changing the predetermined delay amount and compensating the baseband signal again with the changed predetermined delay amount, and performing steps (b) and (c) again to update the correlation value; and (e) selecting a candidate delay amount from the predetermined delay amount according to the correlation value, and compensating the transmitter by using the candidate delay amount.