Luc Montagnier (born 1932) is a French virologist. He discovered the AIDS virus HIV, then encountered international disdain (see AIDS reappraisal) after declaring in 1990 that HIV cannot cause AIDS on its own, but needed a cofactor which he believes is a mycoplasma.

His research was done at the Pasteur Institute in Paris. The identity of the first person to isolate HIV (which develops into the AIDS virus) was previously disputed among Dr. Montagnier and American Robert Gallo. Eventually the two of them agreed to share credit for the discovery of the HIV virus.

"AIDS does not inevitably lead to death, especially if you suppress the co-factors that support the disease. It is very important to tell this to people who are infected. I think we should put the same weight now on the co-factors as we have on HIV. Psychological factors are critical in supporting immune function. If you suppress this psychological support by telling someone he's condemned to die, your words alone will have condemned him." - Luc Montagnier