"France and Angola have had a relationship which has not always been straightforward but we have been trying to strengthen them for several years now," Hollande said when he arrived in Luanda on Thursday evening after visiting Benin.
The Angolagate scandal, which implicated prominent French politicians in illegal arms sales to President José Eduardo dos Santos's government in the 1990s, cast a shadow over relations for some time.
But Hollande's predecessor, Nicolas Sarkozy, started a reconciliation process with a visit in 2008 and dos Santos visited Paris for the first time for 20 years in 2014.
Despite a long civil war, which ended in 2002, dos Santos has been in power for 36 years and the economy has seen rapid growth, almost entirely based on oil, of which it is Africa's second-biggest producer.
Hollande said that the country is important "economically but also politically" and hailed it as a stable presence in a region that is experiencing conflict in the Great Lakes, the Democratic Republic of Congo and the Central African Republic (CAR).
France would like Luanda to send troops to the CAR, where it has intervened militarily, but so far Angola has limited its contribution to a 10-million-dollar (nine-million-euro) donation in 2014.
But the focus of Hollande's visit is business, with Accor signing the hotel deal and construction group BTP Eiffage hoping to win a 180-million-euro contract to build bridges.
The fall in the price of oil has hit Angola's economy and France, whose Total pumps 10 per cent of its production there, hopes to help it diversify.
Agrees concerning aid, visas and military cooperation were to be signed.
Dos Santos's critics are concerned about his human rights record, for example the case of 15 activists in jail accused of plotting rebellion, and income distribution in a country where more than half the population live on less than two dollars a day.
Hollande was to go on to Cameroon to wind up his tour on Saturday.