Australian miner Oxiana Ltd says gold production at its flagship Sepon project in Laos is expected to increase in the second half of the year, and has stuck to its annual gold and copper production forecasts.

Melbourne-based Oxiana reported group gold production of 47,674 ounces of gold, 498,499 ounces of silver, 17,395 tonnes copper and 31,300 tonnes zinc in the second quarter.

Oxiana said gold production at Sepon was impacted by lower grades but was expected to increase in the second half.

For the quarter Oxiana produced 39,274 ounces of gold at Sepon and 79,895 ounces for the first half.

"Gold production is expected to increase in the second half of the year with grades higher in the third quarter and throughput increasing at the end of the wet season in the fourth quarter," the company said.

Oxiana said forecast gold production for the year at Sepon remained at 170,000 ounces.

In the second quarter, the Sepon copper plant produced marginally above nameplate capacity of 60,000 tonnes per annum.

It produced 15,995 tonnes of copper for the quarter and 30,051 tonnes for the half.

The production forecast for the year remained at 60,000 tonnes.