South Korean manufacturers' business sentiment will improve next month as they expect a slight recovery in domestic demand and exports, central bank data showed Wednesday.

The business survey index of manufacturing firms here came to 74 for the upcoming month, up from 71 for August, according to the Bank of Korea.

A reading above 100 means optimists outnumber pessimists, while a reading below the benchmark means the opposite.

An index measuring local firms' sentiment toward exports came to 87 for September, up from 85 the previous month.

A separate index for domestic sales stood at 82 for next month, up from 81 in August.

Amid an anticipated increase in overall sales, local companies also expected their profitability to go up, registering a BIS reading of 89 for September compared with 87 for this month, according to the BOK.

The BSI of non-manufacturing firms rose to 75 for next month from 70 for August.

The monthly index is based on a survey of 2,843 companies throughout the country from Aug. 17 to 24. (Yonhap)