The Labor Department report is scheduled to be released on Friday at 8:30 a.m.
Stocks rallied on Thursday, in part due to a surprise drop in in the weekly claims for jobless benefits. But analysts said the market could reverse course if Friday's jobs report turns out to be worse than expected.
"If it's a nasty loss [of jobs], it would pull the rug out from under the rally," said Al Goldman, chief market strategist at A.G. Edwards.
Another drop in payrolls would mark the first five-month run of job losses since 2003, when the economy was in what economists at the time termed a "jobless recovery."
"Credit-related 'headwinds' and soft final demand imply weak labor demand over the remainder of the year," said Bank of America economists in a research note to clients.
That cut in jobs is likely to bring the unemployment rate up to 5.1 percent from 5 percent.
Some economists held out hope for slightly better news after ADP Employer Services released a separate report on Wednesday showing the economy added 40,000 private-sector jobs in May.
While the ADP report has tended in recent months to overestimate job gains, economists said it could foreshadow a smaller-than-expected decline in the government's payrolls report on Friday.
"Other things being equal, it increases the chance that Friday's official payroll number will beat the current consensus," said Ian Shepherdson, chief U.S. economist at High Frequency Economics in Valhalla, New York.
But he stopped short of predicting the end of payroll declines, adding "we remain of the view that the trend will be downwards for the foreseeable future." Unlike the ADP data, the Labor Department's non-farm payrolls report includes both private and public sector jobs and is generally seen as more reliable by economists.
Indeed, continued weakness in the jobs market "has been foreshadowed by the major leading indicators of employment -- rising initial and continuing jobless claims and household assessments of labor market conditions," said Steven A.
Woods, economist at Danville, California-based Insight Economics.
The brunt of the job cuts this year have come from manufacturing and construction, which has lost about a half million jobs since a housing bubble burst in late 2006.
Typically, in an economic slowdown, the economy loses up to 2 million jobs.
Around a quarter of a million jobs have been lost this year and economists expect more cuts, particularly as consumers -- who fuel roughly two-thirds of economic output -- trim their spending.
--Reuters contributed to this report.