Singapore shares were down 16.84 points, or 0.54 per cent, to 3.083.4 at midday on Friday.
Some 803.9 million shares changed hands, worth $405.1 million.
There were 111 gainers, versus 175 losers.
Global stocks have retreated this week as mixed company earnings and signs of weakness in China's economy added to concern that cuts to US Federal Reserve stimulus will destabilize emerging markets.
The Fed meets next week. Declines in Japanese and Chinese equities also put the regional MSCI Asia Pacific index on track for its longest run of weekly losses in more than 18 months.