H.R.6393: To amend titles V, XVIII, and XIX of the Social Security Act to promote tobacco use cessation under the Medicare Program, the Medicaid Program, and the maternal and child health program.

Quit Smoking for Life Act of 2008 - Amends title XVIII (Medicare) of the Social Security Act (SSA) to cover diagnostic, therapy, and counseling services, furnished by or under a physician's supervision, for cessation of tobacco use. Provides for payment of 80% of the lesser of the actual charge or the fee schedule amount. Eliminates the deductible.

Includes tobacco cessation agents as covered drugs under Medicare part D (Voluntary Prescription Drug Benefit Program).

Amends SSA titles V (Maternal and Child Health Services) and XIX (Medicaid) also to cover counseling and medication for cessation of tobacco use. Requires inclusion of anti-tobacco messages in health promotion counseling as part of quality maternal and child health services.