Military personnel have made more than 200 allegations of rape and other sexual offences against their colleagues in the past three years.
Figures obtained under the Freedom of Information Act showed that 75 allegations of rape and 150 of sexual assault were made to military police between 2011 and 2013. Some 25 rape allegations were made against armed forces personnel in 2013, 24 in 2012 and 26 in 2011. In 2013 there were 52 allegations of sexual assault, compared with 42 in 2012 and 55 in 2011.
The figures were for cases of alleged abuse by Ministry of Defence staff against members of the armed forces or MoD civil servants.
Court-martial results also revealed that five servicemen were convicted of rape and 22 of sexual assault between October 2011 and November last year, the Sunday Times said.
Labour MP Madeleine Moon, who sits on the defence select committee, told the Sunday Times many more sex attacks in the armed forces could be going unreported and that the figures may simply be the "tip of the iceberg".
She said: "What other sector of society would see this number of rapes between colleagues?
"Not enough is being done to make sure that people who join the armed forces are safe from attack and abuse by colleagues."
Under the 2006 Armed Forces Act, commanding officers are required to report only rape and the most serious sexual assaults to military police or the Service Prosecuting Authority, the newspaper said. Lesser allegations, such as groping, can be dealt with by the military chain of command.
In October 2011 Royal Military Police officer Corporal Anne-Marie Ellement was found hanging in her quarters at Bulford Barracks near Salisbury in Wiltshire after she accused two soldiers of rape.
Corporal Ellement, 30, alleged she had been raped by the pair in November 2009 while she was posted in Germany but had been left "absolutely devastated" by the decision taken by military investigators not to prosecute them.
An inquest on Monday was adjourned after MoD officials announced they had found 1,400 unseen files, 29 of which were deemed relevant to the inquest by the MoD. Her family fear a cover-up, which the MoD denies.