Alistair Spagnoletti, 21, of Luton, and Curtis Walker, 23, of Watford, pleaded guilty to controlling a child at Harrow Crown Court.
Callum Ward, 19, of Watford, was found guilty of the same charge.
Police said the men groomed a 17-year-old girl into prostitution in one of the most "damaging" cases of child sexual exploitation they had seen.
Det Sgt Iain MacPherson, of Hertfordshire police, said: "This is one of the most damaging cases of child sexual exploitation we have encountered in Hertfordshire.
"It has also been an extremely complex case. These men had groomed their 17-year-old victim into having sex with men for money which they took, she believed that by providing her with food, drink, drugs, they were looking after her and they were people she could trust.
"The power they wielded over her was so great that she felt she could not support police action against them. Sadly she may never recover from what they have done to her.
"These acts are deplorable and I am in no doubt these men pose a risk to other children. It is right they are now serving time in prison."
Spagnoletti, of Wauluds Drive, Luton, was jailed for six years and eight months. Walker, of Lord Street, Watford, was jailed for four and a half years and Ward, of The Thrums, Watford, was jailed for two years.
Three men have been jailed for sexually exploiting a teenage girl in Hertfordshire.