Have hard-liners lost ground to moderates in Poland?

For the first time since martial law suspended a number of a newspapers, Poland's most influential weekly, the reform-minded Polityka, is back on the streets again.

Polish readers starved of news because of the martial law clampdown were urged to write in frankly describing their emotions and reactions under martial law and their views on reform and solutions to Poland's problems.

Reformers both within and outside the Communist Party are seeing the reappearance of the paper as quite a substantial straw in the political wind that the liberals may well be gaining the upper hand in the protracted struggle to gain leadership of the party. What makes the reappearance of Polityka after a lapse of nine issues so significant (albeit it with a staff depleted by the resignation of six of its well-known writers) is that the virulently hard-line paper, Rzeczywistosc, has apparently not yet come back into circulation. Hard-liners fighting all the way

The outlook of the two papers is symptomatic of the struggle now going on within the communist hierarchy beteen the moderate center and and a strong orthodox authoritarian faction. The hard-liners are fighting all the way to prevent any attempts to return Poland to the reformist course it was pursuing before martial law was imposed Dec. 13.

The hard-line forces comprise a spectrum of conservative and ultra ''left'' opinion, headed by Stefan Olszowski, a prominent member of the Politburo. The group includes leading spokesmen from some of the antireform groups that sprang up in several key regions following last summer's democratizing congress of the Communist Party.

They were associated with Rzeczywistosc, which was suspended along with all other Polish weeklies including Polityka, and other periodicals when the emergency was declared Dec. 13. Some of the principal Warsaw, and few of the regional, dailies have since been allowed to reappear, and permission has been given others to come out in the near future. Most of the weeklies, however, are still suspended.

The leading force, meanwhile, behind Polityka, is Mieczyslaw Rakowski, who is now vice-premier and is the closest social-political adviser to the head of the military council, premier and party chief Gen. Wojciech Jaruzelski. He was named editor in 1958 following the ''October'' reform movement under Wladislaw Gomulka and after Gomulka had closed down the outspoken student magazine Postu because it was too daringly ''revisionist.''

From then on Polityka emerged as a staunchly reformist and often independent but moderate voice which over the years sometimes came into conflict with both government and censorship. It won considerable public confidence and a sell-out print of 350,000 which made it easily the most widely read weekly in the country.

Despite his government post, Rakowski so far remains its editor. His Cabinet appointment a year ago as vice-premier responsible for negotiating with Solidarity and the trade union movement as a whole was seen at the time as an important step toward building a strong moderate consensus. This was seen as the only possible way to avoid confrontation with the new union and to keep the hard-liners at bay. Article extends olive branch

After 2 1/2 months of martial law, this emerges as still the crux of an internal party struggle to try to decide the future of the unions and the other reforms wrapped into the package of ''socialist renewal'' last July.

His front-page lead article in No. 1 of the new Polityka seems to indicate a bid for an effort at understanding under the heading ''the bridge is not yet broken.''

The time had come, he said, to begin an analysis of the last two months in the light of ''the spirit and the letter'' of the (democratizing) resolutions of the (July) 9th congress. Moving the clock forward, not back

Those congress decisions constitute the main plan of the leading half-dozen moderates, the so-called Jaruzelski-Rakowski group in the Politburo, who see ''renewal'' as the unquestionable prerequisite for a reinvigorated and restored party with a credible public image.

''We want no return to the anarchy of that anarchic period before December 1981,'' an official said. ''But equally we want no return to pre-August 1980.''

The battle, in fact, is with those who would put the clock back 18 months or more for another kind of restoration - of a ''Marxist-Leninist'' party cast in the severe Soviet mold.