MPs said that the questions, part of a major study into the causes of Gulf War illness, were designed to prove that the sickness was all in the mind.
Researchers have proposed asking veterans if they experienced sexual harassment, sexual assault, or were "forced to have sexual relations against your wishes", while in the Gulf.
The questions form part of a draft questionnaire prepared and circulated by the Gulf War Study Unit, at King's College Medical School, London. The Independent has obtained a copy.
Last night Dr Simon Wessely, who is heading the study, said it had been decided to drop the questions from the final version of the questionnaire. He said the reason was that the questionnaire was "too long" although he conceded that the questions were "probably culturally inappropriate".
Other questions in the study focus on whether the Gulf veterans experienced bad dreams or flashbacks of what they had seen in the conflict, and whether they bottled up their emotions.
If research concludes that Gulf War syndrome is due to post-traumatic stress disorder or other psychological conditions then the victims are unlikely to win compensation.
Veterans argue that their illnesses were caused by chemicals to which they were exposed in the Gulf.
Dr David Clark, Labour's spokesman for defence, said: "It looks as if they are trying to prove that the Government has done nothing wrong to these men and women. They are coming at it from the wrong angle."
Terry Lewis, the Labour MP for Worsley, is to raise the matter in the Commons after complaints from veterans in his constituency.
"These people have already got problems and many of them will be put off by this type of questioning," he said. "It is concentrated too much on the psychological rather than the physiological."
The King's College study is being funded by a $1m (pounds 600,000) grant from the American Defense Department and has the co-operation of the Ministry of Defence.
Some 10,000 troops will be surveyed, including 3,000 who served in the Gulf, a similar number who served in Bosnia and others who were in neither conflict. The questionnaires are expected to be sent out next month.
Dr Wessely denied that the study was in any way biased but said that the results would inevitably cause controversy.
He said the questions covered the full range of health problems which soldiers were likely to have experienced.
"There is no particular slant," he said. "My job is to get the right answer."
Dr Wessely has already been attacked by groups working with the victims of myalgic encephalomyelitis (ME) for suggesting that the condition, also known as chronic fatigue syndrome, was all in the mind.
Kerry Tolley, spokeswoman for Action for ME, said: "He thinks it's a form of depression, perpetrated by psychological factors."
In July last year, Dr Wessely wrote a controversial article in the Times, in which he said that Gulf veterans were healthier than other people, despite so-called Gulf War syndrome.
Jo Masters, a solicitor with Dawbarns of King's Lynn, which represents many Gulf veterans, said: "The veterans are very concerned about it being labelled as `all in their minds'."Reuse content