SYDNEY AIRPORT earns more money per passenger and provides worse service than any airport in the country, the consumer watchdog has found.

The Australian Competition and Consumer Commission's annual airport monitoring report typically features criticism of service at Sydney. But yesterday's report was particularly harsh and went close to suggesting the airport was abusing its monopoly.

According to the commission's figures, Sydney Airport made more than $14 a passenger in the 2009-10 financial year. That was an 8 per cent increase on the previous year and comfortably the highest margin in the country.

But the airport also recorded the worst ranking on the commission measure of service quality, which takes into account the views of passengers, airlines, and the customs and quarantine officers that work there.

The commission chairman, Graeme Samuel, said Sydney Airport stood out compared to other airports that had responded to concerns about service quality.