A man who got his 11-year-old stepdaughter pregnant and went on to marry her once she turned 18 has avoided jail.

The 58-year-old barber, who cannot be named as it would identify his victim, pleaded guilty to carnal knowledge of the girl when he faced court this morning following 15 years on the run.

Brisbane District Court heard the man was in a relationship with the girl's mother in 1995 when he was 42 and the girl was 11 years old and living in Brisbane.

He claimed the girl entered his room, removed her clothes and got into bed with him during the September school holidays.

He said they had sex, not initiated by him, and she became pregnant.