* Samsung has 1st quarterly operating profit decline in 2 yrs
* Automakers Hyundai Motor, Kia Motors down
* China, US factory surveys crimp risk appetite
SEOUL, Jan 24 Seoul shares touched a 4-1/2 month low on Friday morning due to disappointing Korean earnings reports and concern about factory activity in China and the U.S.
The Korea Composite Stock Price Index (KOSPI) was down 0.7 percent at 1,933.02 points as of 0225 GMT after reaching an intraday low of 1,931.09, its lowest level since Sept. 4.
"The market is pressured by earnings worries, especially after the two largest components in Samsung Electronics and Hyundai Motor recorded worse-than-expected figures," said Bae Sung-young, a market analyst at Hyundai Securities."
In its fourth quarter earnings, announced before the market opened, Samsung Electronics Co Ltd reported a quarterly decline in operating profit for the first time in two years.
The stock gained 0.7 percent on Friday, but was still down more than 4 percent this month on concern over slowing smartphone growth.
Hyundai Motor Co dropped 2.8 percent after posting its first year-on-year fall in quarterly revenue in nearly three years.
Affiliate Kia Motors Corp dipped 2.6 percent after reporting soft earnings.
The U.S. manufacturing Purchasing Managers' Index for January fell in December, a preliminary private survey on Thursday. This came after a worse-than-expected preliminary HSBC China manufacturing PMI that cooled risk appetites.
Foreigners and institutional investors sold a combined net 148 billion won ($137.8 million) of KOSPI shares near mid-session, weighing on the index.
Daelim Industrial Co Ltd tumbled 3.6 percent after it posted a operating deficit for fourth quarter.
Sector peer GS Engineering & Construction Co Ltd , which is issuing convertible bonds to improve liquidity, plunged 7.9 percent. ($1 = 1073.9500 Korean won) (Reporting by Jungmin Jang; Editing by Richard Borsuk)