There are only 13 black or minority ethnic police officers above the rank of PC in the whole of Wales.
Just 1.6% of police officers are BME in Wales, compared to 4.5% of the population.
Tola Munro, the first Welsh president of the National Black Police Association, said lingering institutional racism was one aspect hampering recruitment.
The Home Office said it was "clear that there is more for forces to do".
Under-representation is a problem across the board in England and Wales, according to Home Office figures.
Dyfed-Powys Police is the force with the lowest percentage of BME officers - just 0.9% of its 1,160 officers.
North Wales Police has the third lowest total - 1% of its 1,441 officers.
North Wales Police has two BME PCs while Gwent has a sergeant and 23 PCs and Dyfed-Powys Police has two BME sergeants.
South Wales Police has 52 PCs, eight sergeants, one inspector, one chief inspector and two superintendents.
Mr Munro said he had been doing work in the Maindee area of Newport to promote a career in policing to BME children but forces were not Mr Munro "representing our communities".
Uzo Iwobi, chief executive of Race Council Cymru, said: "It's important that the police service resembles the communities it serves. Something that is really clear is the police need to look at their culture."
Ms Iwobi said a lack of "good news stories" about BME officers progressing through the ranks would not encourage others to pursue a career in policing.
North Wales Police's head of diversity, Gregory George, said: "The force has set up a strategic positive action working group to address this issue of under representation and we actively encourage new recruits from a range of different backgrounds."
Dyfed-Powys Police said a strategy for recruitment was in place to "encourage people from diverse communities to apply".
South Wales Police set up a representative workforce team three-years-ago, aimed at increasing the number of BAME officers and staff.
The force said while the number of applicants had "increased significantly", it recognised there was still "much more to do" to improve diversity.