Disclosed is a transmitter optical module which includes an electro-absorption modulated laser modulating a light into an optical signal through a high-frequency electrical signal; a first sub-mount transferring the high-frequency signal to the electro-absorption modulated laser; and a second sub-mount receiving the high-frequency signal from the electro-absorption modulated laser to terminate the electro-absorption modulated laser. A length of a first wire connecting the first sub-mount and the electro-absorption modulated laser is different from a length of a second wire connecting the second sub-mount and the electro-absorption modulated laser.