The Afghan government is likely to benefit indirectly from the death of Pakistani President Mohammad Zia ul-Haq, and the Soviet Union could find it easier to complete its troop withdrawal from Afghanistan.

Although diplomats said this week they did not expect any major shift in Pakistan's support for Afghan reb-els fighting the communist government following Zia's death Wednesday in a plane crash, they noted the guerrillas have lost their most unwavering supporter in Zia.

"Zia is going to be a hard man to replace in terms of devotion to the mujahideen (guerrilla) cause," a Western diplomat said.

Other analysts added that the country is bound to be diverted from this support as different factions vie for power.

"To some extent the Afghan government will be given breathing space," a senior Asian diplomat said.

The resistance also is likely to be hampered, at least temporarily, by the death of Gen. Akhtar Abdur Rahman, the Pakistani chief of staff who was aboard Zia's aircraft. Rahman coordinated assistance to the rebels and had close personal rapport with all the guerrilla leaders.

With Pakistan investigating the possibility of sabotage in the crash, Afghanistan's government and its chief sponsor, the Soviet Union, are bound to come under suspicion.

Former Secretary of State Henry Kissinger said the Soviets will get "credit" in the region for Zia's death and "are significant beneficiaries." He added, "It reduces Pakistan's capacity to influence the outcome of the Afghan civil war that will inevitably occur in Afghanistan after Soviet troops withdraw."

He also said Zia's death makes it "easier" for the Soviets to continue their withdrawal.

"This makes the supply to resistance fighters more difficult because there will be no really authoritative government in Pakistan for many months, not until the elections," scheduled for November.

President Najibullah of Afghanistan has offered his condolences and expressed hopes for good future relations with Pakistan.

But a Soviet source who declined to be identified, said several high-ranking Afghan officials had expressed "a satisfied reaction" to Zia's death, although he dismissed the possibility of involvement by Moscow or Kabul.

"Zia had so many enemies, not only Afghanistan and the Soviet Union," he said.

India has fought three wars with Pakistan and relations recently have been tense. Zia also had many internal opponents opposed to his harsh Islamic rule.

A senior U.S. official pointed obliquely toward possible Soviet involvement, saying in Washington, "The Soviets have been attacking and warning Zia for the past week, so they have some explaining to do."

As the Soviet troop withdrawal from Afghanistan has picked up steam, there have been increasing accusations by Moscow and Kabul that Islamabad was violating the Geneva accord which established the timetable for the pullout of 115,000 Soviet soldiers, scheduled to be completed by Feb. 15.

Soviet Foreign Minister Eduard Shevardnadze assured Najibullah during a Kabul visit last week that Moscow would take "steps" to reduce the alleged violations, but Soviet oficials said the moves would only be political and diplomatic.

For Kabul residents, Zia's death meant more uncertainty.

"We cannot say that this is good news for Afghanistan," said one government employee. "Maybe someone will come into power who is an even fiercer supporter of the mujahideen."