Donald J. Devine's departure as producer-director of the federal civil service could spell even more trouble down the road for government employes--believe it or not.

Federal and postal workers who started celebrating yesterday when Devine withdrew his nomination for a second term as head of the Office of Personnel Management need to ask the next obvious question: Who comes next?

If the White House picks a bland caretaker to run OPM for the next 3 1/2 years, government workers will have fewer nightmares about pay cuts, reduced pensions and unemployment.

But the White House could send up a nominee who is politically well-connected, and who knows how to win friends and influence people. If so, some of Devine's programs, which won wide support outside Washington, could become reality, even if Devine isn't around to see it happen.

The former University of Maryland political science professor is regarded as a top flight political analyst and political strategist. But even his biggest fans concede that he was no politician in that job.

Devine's reconfirmation chances were dashed when acting OPM director Loretta Cornelius told a Senate subcommittee that she was unaware Devine had secretly delegated himself power to run the agency after his term expired and he became her temporary assistant. She said Devine later asked her to say, if questioned by the subcommittee, that she knew of the delegation of authority.

Devine's problems with Congress, many civil servants and all government unions, started long ago when he began proposing changes that would have been unpleasant for federal workers.

But it was often the abrasive, stick it in your ear style he and aides adopted with important members of Congress that doomed the proposals. He was so unpopular with Democrats on the House Post Office-Civil Service Committee that it was said they would vote down a resolution praising motherhood, puppies and clean air if Devine proposed it.

"If Scotty Campbell OPM director under President Carter had been in the job and proposed the same things, he probably would have gotten them through Congress," a congressional aide said some time ago.

Campbell, also a political science professor, had the skills of a politician, including a willingness to compromise.

But Devine and his associates "saw every issue as total war, liberals versus conservatives," a former OPM executive said yesterday.

Spokesmen for several federal union leaders said privately that Devine "was the best thing that ever happened to us," in the sense that he served as an easy to dislike lightning rod, whose actions united often warring unions and pressure groups.

The pressure feds feel will probably ease with Devine gone. But if a smooth-talking conservative is his successor, the post-Devine holiday for feds could be a short one.