Researchers at Guy's, King's and St. Thomas's Hospital in London said privates who served in the Gulf War were 20% more likely to report health problems than non-commissioned officers and 70% more likely than other officers.
Dr Khalida Ismail, of the Gulf War Illness Research Unit, said: "Rank was the main occupational factor associated with both psychological and physical ill health in Gulf veterans."
Dr Ismail and his colleagues studied more than 3,000 veterans, who had served in the war between September 1990 and June 1991, six or seven years after they returned.
Fifty-seven percent of the veterans had left the armed forces at the time of the study which was adjusted for the numerical imbalance between lower ranks and officers.
Dr Ismail said: "This study suggests that rank, and perhaps being deployed as an individual reinforcement in a combat role, are associated with poor health in UK Gulf veterans."
Men and women who had left the armed forces at the time of the study reported worse health than those who were still in the service.
Dr Ismail said: "Gulf veterans who were divorced, separated or widowed were around twice as likely to report psychological problems than married or cohabiting veterans."
No Gulf War Syndrome link
But the researchers said rank was not linked to so-called Gulf War Syndrome.
This is the controversial theory that the health of Gulf War veterans was in some way damaged as a result of their deployment in the 1990 conflict.
Certainly, a high number of veterans have complained of chronic fatigue, infertility and mental illness since their return to the UK.
Some experts believe that this may be linked to immunisation or exposure to pesticides or organophosphates. Others, however, refuse to accept that the syndrome exists at all.
Most military staff, regardless of rank, were exposed to the same elements and given the same immunisations.
The research was published in the Journal of Epidemiology and Community Health.