A BRISBANE Uber driver who questioned how a lesbian passenger had sex has been fined $300 and avoided conviction.

Umar Subi Gammeda was initially charged with deprivation of liberty after allegedly detaining the customer for more than an hour in August 2017.

But prosecutors withdrew that charge on Friday morning due to lack of evidence.

The 46-year-old instead pleaded guilty in Brisbane Magistrates Court to causing a public nuisance.

The court heard he had been chatting with his 25-year-old passenger about whether she was married after collecting her from her Paddington home.

As they drove to Fortitude Valley the woman told him she was gay.

Subi Gammeda responded that homosexuality wasn't condoned in his home country of Ethiopia.

He then asked how she had sex with her girlfriend, which was the basis of the public nuisance charge.

He did not comment to media while walking from court after being fined.