The number of complaints from Black, Asian, minority ethnic (BAME) service personnel is disproportionately higher compared to their representation, according to the Service Complaints Ombudsman for the Armed Forces.
The Defence Committee heard how BAME groups in the military were more than twice as likely to complain of bullying, harassment and discrimination, compared to white personnel.
Service Complaints Ombudsman Nicola Williams, told the Defence Committee: "There is a disproportionality, for a number of reasons.
"The particular figure I can remember is with Black, Asian, ethnic minority staff in terms of claims of bullying around bullying, harassment and discrimination.
"Fifty-seven per cent of complaints from that grouping [BAME] are around bullying, discrimination and harassment, as opposed to 21% of white complainants."
Mrs Williams added there is "similar disproportionality with regards to gender".
When looking at why the BAME figures are disproportionate, Mrs Williams said: "It could be because they do get more bullying, discrimination and harassment.
"But we also know with the AFCAS figures [Armed Forces Continous Attitude Survey] that of the number of people that could make a legitimate complaint, only a very small proportion of those actually do make a complaint.
"The majority of those when they are asked 'why don't you make a complaint?', say things [like] 'I'll be victimised for making a complaint', 'my life will be made a misery if I make a complaint'.
"It makes you wonder if all the people that could make a complaint, both female and ethnic minority, [if they] did make a complaint that would be even more disproportionate."
Mrs Williams added said she was waiting for more information from the Ministry of Defence (MOD).
The 2017 Annual Report described the Armed Forces Complaints System as not "effective, efficient or fair".
The MOD has carried out a review to try to establish the reasons behind that disproportionality, however the results are not yet available.