The FTSE 250 group blamed delays to planned operational improvements as it reported total gold production of 117,720 ounces (oz) in the three months ended September 30 versus 156,530oz in the year-ago period.
It was, however, a pick up on the 92,800oz it mined in the second quarter.
Centamin now expects annual production of around 480,000, down from its earlier target of between 505,000-515,000oz.
“These results are a demonstrable operational improvement on Q2. We are extremely pleased with the operational performance from the open pit,” said chief executive Andrew Parley.
“We are through the transitional ore, grades are improving in line with the mine plan and will continue to through the fourth quarter.”
He added: “The underground improvements have been very encouraging and are continuing. Our focus remains on achieving optimal and consistent performance.”