SANTIAGO, Chile (AP) _ President Augusto Pinochet replaced the army member of the ruling four-man junta with the director of secret police and retired nine generals Wednesday in what appeared to be a move against military men at odds with him.

Pinochet, the 70-year-old army commander, named Lt. Gen. Humberto Gordon, director of the secret police agency and one of his most loyal aides, to represent the army on the junta starting Dec. 11.

He will replace Lt. Gen. Julio Canessa, who was being assigned to ''new functions of presidential confidence,'' according to a government announcement. Canessa was named to the junta nearly a year ago.

The military retirements, effective Dec. 31, were announced in an armed forces communique which said they were routine.

Among those retired were Maj. Gen. Luis Danus, commander of the southernmost military region and Brig. Gen. Gaston Frez, commander of the northernmost region.

Danus and Frez were known to favor talks with the non-Marxist civilian opposition about a transition to democratic rule. Danus has said publicly that Chile's month-old state of siege is unnecessary in his region.

Also retired is Maj. Gen. Alejandro Medina, chairman of the joint chiefs of staff. While not as outspoken as Danus and Frez, he was not considered to be personally loyal to Pinochet.

The 53,000-man army has been Pinochet's power base since he seized the presidency from Salvador Allende, an elected Marxist, in a 1973 coup. Among Latin American armies, it has one of the strongest traditions of absolute loyalty to its commander.

Pinochet has hinted at prolonging his 13-year presidency beyond his current eight-year term, which ends in 1989.

Chilean opposition leaders are seeking talks with junta members to try to turn a 1989 plebiscite, in which Pinochet seeks to be the lone candidate in a yes-or-no vote, into an open presidential election.

On Tuesday, Gen. Fernando Matthei, the air force commander and junta representative, said he favored such talks and said they should begin ''with some haste.''

Gordon, the new man on the junta, has directed the secret police agency since 1980. Known as the National Information Central, the agency has been widely accused of torturing arrested dissidents to obtain information. It reports directly to the president.

Gordon has denied his police practice torture. In brief remarks to reporters after his new appointment, he said he was leaving the police post ''with a clean and peaceful conscience.''

Army Brig. Gen. Hugo Salas Wenzel, Gordon's chief deputy, was named the new director of the secret police.

Pinochet, who controls the military promotions board, often keeps trusted generals on active duty after their normal retirement following 41 years of service. Gordon is one of several in that category, along with Lt. Gen. Santiago Sinclair, who was confirmed as army vice commander.

Danus and Medina were retired upon completing 41 years, but Frez had three years of active duty remaining.

Twelve army officers were promoted to general, raising the number in that rank to 54. Military specialists say Pinochet finds it easier to control a larger group of generals. Since the 1973 coup, their number has grown from 25.

In addition to Gordon and Matthei, the other junta members are Navy Adm. Jose Toribio Merino and the comander of the national police, Gen. Rodolfo Stange.