Hankook Tire Co, the country's top tyre maker, fell 3.08 percent to 12,600 won after it said its operating profit in July-September fell 11.13 percent from a year earlier.
But tech stocks such as Hynix Semiconductor Inc extended a rally as investors saw them as undervalued, betting on improved earnings prospects for as early as the next quarter.
The benchmark Korea Composite Stock Price Index (KOSPI) fell 0.29 percent to close at 1,218.47.
"With the market rising so much throughout last week, it was time for a correction," said Kim Seong-ki, a fund manager at Chohung Investment Trust Management.
"US inflation is still a worry," he said, noting that disappointment about US jobs data had also weighed on shares.
South Korean shares jumped 7.1 percent last week to strike a three-week closing high on Friday.
Several of the stocks that posted solid gains last week were among those on the wane on Monday.
Top local lender Kookmin Bank fell 0.78 percent to 63,300 won, while department store operator Shinsegae Co Ltd fell 0.63 percent to 397,500 won.
SK Telecom Co, the country's top wireless operator, fell 1.58 percent to 187,000 won.
Investors were also cautious after data on Friday showed US employers added far less workers to non-farm payrolls in October than economists had expected, while wages grew at the strongest pace in 2-1/2 years.
Hyundai Motor Co, South Korea's top auto maker, fell 1.22 percent to 80,900 won.
Disappointment over earnings also sent some shares lower. Hyundai Mipo Dockyard Co Ltd fell 2.67 percent to 62,000 won after posting a larger-than-expected fall in earnings on Friday.
Investors also pared back expectations for other shipbuilders, pushing Samsung Heavy Industries Co Ltd, the world's third-biggest shipbuilder, down 4.23 percent to 13,600 won.
Online game developer NCSoft Corp fell 7.22 percent to 90,000 won as investors fretted earnings in the current quarter would be hit by increased marketing costs for the launch of games in new markets. But techs rose as investors were optimistic about future earnings. Hynix Semiconductor rose 4.02 percent to 22,000 won. The world's No 2 memory chip maker has risen 15.8 percent over the past six sessions after shedding 17.1 percent last month.
Shares in retailer Hyundai Department Store Co Ltd rose 1.57 percent to 77,400 won after it said its third quarter net profit surged 70 percent to 30.2 billion won from 17.8 billion won a year earlier.
Pharmaceutical stocks extended a recent rally as a couple of positive earnings results revived expectations about the profit outlook for the sector.
Hanmi Pharmaceutical Co Ltd surged 8.94 percent to 128,000 won, after earlier hitting an all-time high of 129,000 won.
The rally among drug makers was the biggest factor in a 0.84 percent gain in the junior Kosdaq market, which ended at 622.59, its highest close since ending at 631.4 on July 19, 2002.
Foreign investors, who account for around 40 percent of local market capitalisation, were net buyers for a fifth consecutive session, purchasing a net 6 billion won ($5.71 million).
Trade volume reached around 343 million shares worth 3 trillion won compared to 400 million shares worth 3.7 trillion won on Friday. Decliners edged out gainers by 418 to 319 with 83 titles ending flat.
Institutional investors bought a net 11.7 billion won, while retail investors sold a net 9.4 billion won.
The December KOSPI 200 futures index fell 0.90 point to 156.85, while the underlying KOSPI 200 spot index fell 0.53 point to 156.75.