Abstract: The correlated tuning theory for dual - frequency dye lasers has been used to develop a new Michelson-type of frequency-choosing resonator for dual-frequency without any special beam separator in the cavity. The oscillation and amplification of dual-frequency dye laser with common line, wide tuning range, adjustable power-ratio and narrow linewidth have been realized experimentally , and a high power of pulse energy 12-13 mJ was achieved.