The invention discloses a system and method for calibration of timing mismatch for envelope tracking transmit systems. One embodiment of the present invention relates to a system for calibrating of timing between an amplifier input signal and a modulated supply power. The system includes a supply modulation component, an error metric component, and a delay determiner. The supply modulation component provides the modulated supply power and the amplifier input signal according to an input signal and a set delay signal. The error metric component provides information from a transmitted amplitudesignal and a received amplitude signal. The delay determiner generates timing adjustments in the form of the set delay signal from the error metric information.