A US man has been ordered to continue paying child support even after DNA evidence proved he is not the father of his ex-wife's child.

Chris Atkins from Denver, Colorado separated from Lori Lonnquist when his daughter was two and half and began paying $960 a month in child support.

The 48-year-old father discovered he was not the girl's real father when she was 11-years-old after Lonnquist told him she wanted to change her daughter's last name because she was getting remarried.

When the Colorado father refused to the name change, Lonnquist told him the truth.

A DNA test proved he was not the girl's biological father, prompting him to revoke his obligation of paying child support.

However, under Colorado state law because his name remains on the birth certificate he is legally obliged to keep up his monthly payments.

Lonnquist told a Fox News reporter she didn't feel guilty collecting money from Atkins even though he is not the biological father of their child.

"No not really, he wants to be a jerk to me I can be a jerk right back," she said.

Atkins has not had contact with his now 15-year-old-daughter for almost four years after his ex-wife broke a custody order and refused him access, while still enforcing his monthly payments of $960 a month.

The child's real father Logan Doolen has also become reacquainted with his daughter.

When Atkins eventually got his day in court, a judge dismissed his DNA evidence because he had not gone through the correct submission procedure.