Venezuelan President Hugo Chavez declared, as he stepped off the plane, that he returned in better condition than he was in when he left.
The 56-year-old leader underwent an operation in Cuba a month ago for a cancerous tumor in his pelvic area.
Chavez, who was welcomed at the airport by members of his cabinet and top military officials late Saturday, said he was confident of a quick recovery.
"I underwent examinations and I must tell you that doctors did not find any malignant cells in any part of my body," the president told local television.
He cautioned, however, that there existed the risk of a relapse and predicted new medical procedures that he did not identify.
"We will conquer this disease with the help of God and medical science in order to continue paving the way for a new motherland," he promised.
The president, who is known for his flamboyant political style, said Venezuela "cannot lose its way" or "become a colony" again but did not elaborate.
On Friday, Chavez said he had "successfully" finished a first round of chemotherapy and was preparing for the second round, but did not disclose his treatment schedule.
"There will be several rounds in order to win this battle and eliminate all risk of malignant cells." He also vowed "unsurpassable" courage in his battle against the cancer.
The Brazilian official news agency reported earlier this month that Chavez will undergo new cancer treatment in Brazil after his treatment in Cuba.
Chavez spoke with Brazilian President Dilma Rousseff to work out details of the treatment that will take place at a Sao Paulo hospital, Agencia Brasil reported without disclosing its sources.
The Venezuelan president had asked the National Assembly for permission to travel to Cuba to continue treatment following the June 20 operation.
To lawmakers he described the chemotherapy as the "second stage of this slow and complex process of recovery."
Though the National Assembly unanimously approved his travel request, needed for the president to leave the country for more than five days, opposition leaders insisted it was unconstitutional for Chavez to continue to exercise executive authority from Cuba.
Critics of the president have demanded more details about his cancer, as well as answers to why he cannot be treated in Venezuela, where authorities say they have created a quality health care system.
The Venezuelan government has not explained the extent of Chavez's cancer or provided any other details about the disease.
Cuba, the America's only one-party communist regime, is Chavez's closest regional ally.
Chavez, in power since 1999, is his party's candidate for the 2012 presidential election, seeking a third six-year term in office.