Methods and systems for blocker and/or leakage signal rejection by DC bias cancellation are disclosed and may include undersampling a received signal including a desired signal and an undesired signal. A biasing current in the wireless system may be utilized to reduce a measured DC signal generated by the undersampling of the received signal. The received signal may be undersampled at a frequency of or an integer sub-harmonic of the undesired signal, which may include a leakage signal and/or a blocker signal. The DC biasing current may be controlled utilizing successive approximation, control logic and a digital to analog converter. The output DC voltage may correspond to said undesired signal, and the received signal may be undersampled utilizing a mixer.