Oman International Bank posted nine-month net profit of 15.55 million rials on Monday, down 27 percent from the same period last year.
The bank did not offer a breakdown of its results.
Oman International said previously it made 11.83 million rials in the first half of 2009, which based on the result posted on the Omani bourse, would put its third quarter net profit at 3.72 million rials, according to Reuters calculations.
That is down 37 percent from 5.9 million rials a year ago.
Two analysts had forecast third quarter earnings of 5.84 million rials and 5.74 million rials, according to a Reuters poll.