Abstract: An aspect of the present disclosure is related to a method for measuring and controlling linear chirp level of ultrafast laser pulse. The method includes steps as follows. A carrier-envelope phase-chirp (CEP-chirp) relation which serve as a chirp monitor is extracted, in which the CEP-chirp relation is generated from an ultrafast laser pulse. A linear chirp level of a target pulse is measured in response to the CEP-chirp relation. According to the measuring with respect to the linear chirp level of the target pulse, a dispersion element which the ultrafast laser pulse passes through is varied to control and stabilize the linear chirp level of the target pulse.