Lt. Gen. Chon Doo Hwan, South Korea's military strongman, has ordered all South Korean newsmen and broadcasters who have resisted censorship or sought freedom of the press to be purged from their jobs by Aug. 10, diplomatic sources disclosed here today.

[The Culture Ministry announced Thursday that the government has closed down 172 periodicals as part of its anticorruption drive, Reuter reported. A ministry spokesman said they were all corrupt, lewd or vulgar causing social decay and juvenile delinquency.]

Those who are not purged, as well as those hired to replace the ousted journalists, will be required to attend a training center to "reeducate" them, all South Korean newspapers, news agencies, and broadcasting stations were informed.

Mass media companies were ordered to describe the purge as a "self-purification" drive, and to submit names of those to be fired, diplomats said.

They were told that their lists would be expanded or replaced by purge lists drawn up by the nation's ruling junta-like committee if "self-purification" fell short of the military's standards.

Although South Korean media have been subjected to varying degrees of censorship over the years, no previous South Korean government has ordered every news organization in the country to purge employes considered undesirable by the government.

The first hint that the South Korean public got of the impending purge came this afternoon as newspapers published on their front pages a resolution that the presidents and publishers of the news organizations were ordered to adopt.

The Korean Newspaper Association adopted the resolution yesterday and the Korean Broadcasters Association followed suit today.

The resolution said that the nation's mass media had "come to realize that nothing is more important than the Maintenance of national security against North Korea and the preservation of (domestic) order and peace."

"Always giving priority to the national interest, we firmly believe that the social purification campaign must be pushed at the national level and that the press must actively participate in this effort . . . We will do our utmost to voluntarily eliminate whatever obstacles we may have in journalistic circles as well as irregularities in our effort to successfully attain our historic goals of national security and social purification," the resolution said.

The Ministry of Culture and Information issued a directive to all news organizations listing four reasons for which journalists could be purged. They included newsmen who initiated or took part in a sit-in strike of May 19 to 28 that was conducted to demand freedom of the press; journalists who actively resisted military censorship at any time since it was imposed Oct. 27, the day after president Park Chung Hee was assassinated; saboteurs, and corrupt journalists who have taken money from business men, politicians, or government officials in connection with their work.

Mass media companies were ordered to draw up their own lists of employes and executives to be fired and submit them to the Ministry of Culture and Information by Aug. 10.

The purge comes on the heels of a campaign of arrests, intimidations, and removals of newsmen from government-owned mass media. It appears calculated to weaken the media in such a way that even if formal controls are lifted at some point in the future, the media would be subservient to Chon and the military rulers.