The government published yesterday its first solid statistics on the nation's job picture since the April Teamsters' strike, showing that the economy clearly is slowing from its vigorous pace earlier this year.

Although the figures showed the nation's jobless rate was unchanged in May at 5.8 percent of the Work force, job growth in the economy was weak.And the workweek for rank and file production workers was shorter than before the strike.

Janet L. Norwood, commissioner of labor statistics, told a hearing of the congressional Joint Economic Committee the May figures show that "a clear slowdown in employment growth has occured since March."

The White House, which only a few weeks ago had been worried that the economy might be overheating, welcomed the May figures, but disagreed with assessments by some private economists that a recession may be underway.

Jody Powell, President Carter's press secretary, said the figures "are consistent with our view that economic growth is slowing, but that a recession can be avoided." Powell termed the sluggish job-growth "encouraging."

The figures were significant because they provided the first clear picture of the nation's job situation since the Teamsters' strike began. The impact of the walkout has clouded most key economic indicators for weeks.

The employment survey published in April had showed the total number of jobs in the economy plunged by 668,000 during that month - its steepest drop since 1968 - but the figure was distorted by the strike and the April holidays.

Analysts had been looking for the May figures to show a sharp rebound in job growth, and a snapback in the closely watched index of aggregate weekly hours, which had plummeted by 1.8 percent in April.

However, yesterday's report showed overrall employment up only 144,000 jobs, while the index of weekly hours rose 1 percent - to a level that still was below its March benchmark.

Another key measure, the number of industry payroll jobs, rose by 171,000 in May after edging up a scant 4,000 during April. And employment in the construction industry grew by 65,000 jobs, reversing a previous decline.

However, government analysts said both figures were bloated by an increase in the number of workers involved in highway and street construction - probably the result of pothole-filling in the wake of the severe winter storms.

Employment in the key manufacturing sector edged down again in May for the second month in a row, returning to its February levels. And the workweek in heavy industry shrank visibly.

For all the weaking apparent in the May figures, the modest growth in employment was enough to accomodate new job-seekers. The size of the civilian labor force - job-holders and job-seekrs combined - grew by only 136,000.

Along with that for the overrall economy, the jobless rates for most individual categories of workers remained unchanged from April's levels. The jobless rate for adult men actually edged down to 3.9 percent, from 4 percent before.

However, a major exception was in the jobless rate for teenagers, up to 16.8 percent in May, from 16.5 percent in April. And the unemployment rate for black teenagers rose to 36.9 percent, from 34.5 percent in April.

Teenagers traditionally are among the first groups to suffer when job growth begins to slow. The department's report showed there were 1.6 million teenagers out of work in May, of which 391,000 were black.

The May figures on the job situation marked the tenth month in a row that the unemployment rate has hovered in the 5.7 to 5.9 percent range. The jobless rate has been on a plateau since last summer, when it fell from 6.2 percent.

By the measure used by most economists, the nation now is at or near the so-called "full employment" level - the lowest that joblessness can be reduced through general economic stimulus measures without fueling new inflation.

The May report brought the total number of persons out of work to 5.9 million. CAPTION: Graph, no caption, The Washington Post