January's job losses were worse than the 525,000 that had been forecast by Wall Street economists, who also had expected the unemployment rate to come in lower at 7.5 percent.
Last month's job reductions were the largest since 602,000 in December 1974, while the jobless rate reached its highest level in more than 16 years.
"The economy is just falling into oblivion and it will get worse," said Greg Salvaggio, vice-president for trading at Tempus Consulting in Washington, shortly after the jobs report was issued.
Others agreed, saying it intensifies pressure for the government to try something to prop up the economy.