Hundreds of thousands of Venezuelans had thronged the streets of Caracas to bid a final farewell to the man who ruled the oil-rich South American country for 14 years.
"I pledge allegiance in this life and what we are bringing to this command post is a Christian leader and the commander in chief of the Venezuelan armed forces," Chavez's handpicked heir acting President Nicolas Maduro exclaimed excitedly.
Friends and family joined high-ranking government and army officials in surrounding the coffin draped with a Venezuelan flag as Chavez was entombed.
Official television coverage, streaming the processions throughout the day, cut the footage just as Chavez was set to be laid to rest.
The army barracks-turned-museum will open to the public from Saturday and the government expects the mausoleum to become a "place of pilgrimage for the world's revolutionaries."
Earlier, a black hearse loaded with the casket made its entrance through the gates of the barracks, and several senior military commanders carried the coffin down a red carpet.
"Our people can be absolutely sure that we won't fail them, we will build Bolivarian socialism... following the comandante's instructions," the late president's older brother Adan Chavez spoke just before the coffin closed, as he choked up and could not finish his speech.
Chavez succumbed to cancer on March 5 at age 58, plunging a deeply polarized Venezuela into mourning amid growing uncertainty over its future.
"We came for the love and loyalty. Life will continue to remind us of Hugo Chavez, the man who opened our eyes and roads," said Maria Ruiz, a local official of the ruling PSUV party who travelled from the northern state of Carabobo.
The funeral procession had started two hours earlier, after a mass and a solemn ceremony in the courtyard of the military academy, which for nine days and nights saw throngs of Venezuelans come pay their last respects.
The "commandant" was laid out in an olive green uniform and wore his trademark red beret.
His daughter Maria Gabriela, donning dark glasses, broke through the applause to thank her father for "giving us the homeland back" and promised to defend his legacy, as Chavez's mother wept incessantly.
After a mass, the casket was loaded into a black hearse for the 12-kilometer (7.5-mile) procession by foot, motorcycle, car, jeep and on horseback to the barracks.
Huge crowds of hundreds of thousands of supporters -- many sporting red shirts bearing Chavez's likeness -- watched as the hearse, flanked by riders in ceremonial red military uniforms on horseback, made its way slowly down the Paseo de los Proceres, a boulevard honouring the country's founders.
"I came because he is our president," 51-year-old Judith Santana told AFP. "The best tribute we can pay tribute is to keep fighting for our revolution and to be happy, not sad."
The march resembled last week's seven-hour procession during which Chavez's coffin was transferred to the academy from the military hospital where he died.
Communications Minister Ernesto Villegas said the government had scrapped plans to embalm Chavez "like Lenin" and put him on permanent public view.
"We have ruled out the option of embalming the body of comandante Chavez after a Russian medical commission report," that determined the procedure would require the body to be sent to Russia and stay there for at least seven months, Villegas wrote on Twitter.
Some have also suggested that Chavez be buried in the National Pantheon next to South American independence leader Simon Bolivar, Chavez's personal hero and the inspiration of his leftist movement.
On Tuesday, the ruling party postponed debate in parliament on a constitutional amendment that would make this possible without waiting 25 years.
Venezuelans will vote for a new president on April 14.
In the running are Maduro, Chavez's handpicked successor, and opposition leader Henrique Capriles, whom Chavez beat in October elections.