A semiconductor laser apparatus comprises a first semiconductor laser device that emits a blue-violet laser beam, a second semiconductor laser device that emits a red laser beam, and a conductive package body. The first semiconductor laser device has a p-side pad electrode and an n-side electrode. The p-side pad electrode and n-side electrode of the first semiconductor laser device are electrically isolated from the package body. The p-side pad electrode of the first semiconductor laser device is connected with a drive circuit that generates a positive potential, while the n-side electrode thereof is connected with a dc power supply that generates a negative potential.