About 1.5% of Wiltshire Police officers are black, which the force described as a "disappointing position" to be in.
Sgt Ronnie Lungu, 40, was promoted from constable rank after a tribunal found he had been discriminated against.
The force said opportunities to promote minority officers from within were "quite limited" due to low numbers.
Wiltshire Police currently employs 14 black constables and two black sergeants, according to a Freedom of Information (FOI) request by BBC Wiltshire. It has 1,039 officers in total.
In April, Sgt Lungu - who joined the force in 2003 - claimed he had been passed over for promotion because of his race and a Bristol tribunal ruled in his favour.
Kier Pritchard, temporary assistant chief constable, said: "At this stage we have a small number of officers and staff who are from Black Minority Ethnic (BME) communities, so therefore our opportunity to be able to promote from within, and actually move our staff to higher positions of supervision and management, is actually quite limited and quite restricted for us."
He added it was important to understand from BME communities why there had only been "a small number of applications" for people to join the service.
Jabeer Butt, deputy chief executive of the Race Equality Foundation, said there was "a long way to go" to ensure police forces represented their communities and offered equal opportunities to progress within the ranks.
"It's also quite clear that some of the discriminatory practices that have been around for a while still operate and we still have racism operating within the police force [nationally]," he said.
A police officer who took Wiltshire Police to a racism tribunal is the only black officer to be promoted within the force in the past five years.