A driving apparatus and a driving signal generating method are provided. The driving apparatus includes a timing controller, a driver, a switch and a resistor. The timing controller generates a bi-direction lock signal. The driver receives a differential signal pair. The switch is turned on or cut off according to an eye diagram detection result of the differential signal pair. According to the bi-direction lock signal, the timing controller and the driver are used to: operate a first clock and data recovery (CDR) operation on the differential signal pair during a first time period; set setting parameters of an output differential voltage, a pre-emphasis circuit and an equalizer according to the eye diagram detection result and an on/off state of the switch, and perform a second CDR operation during a second time period; and drive a display according to the differential signal pair during a third time period.