Mubarak diverging from Sadat - but not Camp David

President Hosni Mubarak's first policymaking address has revealed how different he will be from his predecessor, despite his adherence to the peace the late President Anwar Sadat made with Israel.

The Egyptian President's 45-minute speech at a joint session of parliament showed a remarkable awareness of public criticism to Mr. Sadat's domestic and foreign policies. It also showed how determined he is to respond to popular demands for improving the economy.

Stressing self-reliance, he said, ''We are all citizens, not dependents.''

He vowed ''not to commit myself to what I cannot implement, hide the truth from the people, or be lenient with corruption and disorder.''

In sharp contrast to Sadat, who always departed from his text and elaborated for several hours, Mubarak gave a short, concise prepared address reflecting the ex-officer's sense of discipline, accuracy, and straightforwardness.

The new leader was greeted at the assembly with a long standing ovation, and his audience responded to the strong nationalistic tone of his speech with enthusiastic calls of ''Long live Egypt!''

President Mubarak outlined his government's policy along the following lines:

* Economy: Without referring to Mr. Sadat's long-unfulfilled promise of prosperity, Mr. Mubarak said economic problems will take top priority because ''the success of our march will depend on the firm confrontation of economic problems.''

Priorities include directing local and foreign investment to development, solving an acute housing problem, rechanneling subsidies to ensure the needy receive them, and ''eradicating'' private and public expenditure on luxuries.

He also promised to do something to ''compensate'' for the large numbers of skilled workers who must go to other Arab countries to find work, to soften the effect of imports on domestic industries, and to ''consolidate'' the public sector.

Stating that the people should reap the fruits of peace, President Mubarak said there was no going back on Sadat's ''infitah'' economic open-door policy encouraging foreign investment. However, the emphasis now will be different, he said.

''Infitah means projects will be aimed at meeting the basic needs of the working masses, not producing luxury goods that only a minority can afford to buy.''

* Egypt's regional role: ''Egypt is an Arab and African state . . . located in the heart of the Arab nation and the Islamic world,'' said Mr. Mubarak. He supported relations with ''brotherly'' Arab and African peoples.

He also referred to Egypt's peace with Israel as a ''strategic commitment and not a tactical stand.''

Referring to preparations for Israel's last withdrawal from Sinai, scheduled for April 25, the President, who was commander of the Egyptian Air Force during the last war with Israel, assured Egyptians that ''voices raising doubts about withdrawal and subjecting it to bargaining should be discarded.''

* Relations with superpowers: Mubarak praised nonalignment, a term deliberately shelved during Sadat's time, as a policy to which he would adhere.

President Mubarak said Egypt's relations with both superpowers will depend on the goodwill of each, and their willingness to respect Egypt's sovereignty and integrity. Egypt refuses ''to revolve in the orbit of another state or becoming part of its strategy,'' he said.

* Domestic politics: Mubarak seemed to confirm speculation that he is aiming at a national front formula grouping the ruling National Democratic Party, and two small left-of-center parties, the Liberal Socialist and the Socialist Labor parties.

In preparation for the changes expected to take place soon, a Cabinet reshuffle may soon take place involving ministers in charge of the economy, finance, and public services, according to well-informed sources.

The President might also appoint a new assistant to replace Sayed Marei, Sadat's son-in-law, who resigned recently. The Monitor has learned Mubarak has already nominated three counselors to replace a council of advisers Sadat had appointed. The three are: former Prime Minister Mustapha Khalil, known to adopt a moderate pro-Arab line; onetime Prime Minister Abdul Aziz Hegazi, a liberal economist with strong Arab ties; and Mamdouh Salem, former prime minister under Sadat and minister of interior before that.