Samim Yakubi, aged 40, was found to have discriminated against 71-year-old Rita Nicholls contrary to the Equality Act 2010.
A court heard Yakubi, a private hire driver for Wednesfield Radio Cars, initially lied about his reasons for failing to allow Ms Nicholls and her dog Charlie into his vehicle.
The taxi had been pre-booked on October 4 last year and the company told Ms Nicholls, who had used the firm before, would have a guide dog.
Yakubi arrived in Market Street, Wolverhampton, but when he realised Ms Nicholls had a guide dog, he told her there had been a mistake and he was there to collect someone else before driving off.
It was observed by a friend and she complained to Wolverhampton council.
In interview Yakubi, of Hobgate Road, Heath Town, revealed the real reason he drove off was because he was worried the dog would urinate in his car and leave hair on its interior.
Magistrates fined Yakubi £80 and ordered him to pay costs of £400 and a victim surcharge of £30 after he pleaded guilty to the offence.
Wolverhampton council will review his private hire licence which could lead to him being taken off the road.