The vaccines will be delivered to the "competent Angolan authorities in a ceremony with the Ministry of Health," the Portuguese Foreign Affairs Ministry said in a statement.
The document added that the 50,000 doses will be "accompanied by the necessary material for their administration," including syringes and needles.
The Portuguese government has made a commitment to provide at least 5 percent of its vaccine batches to Portuguese-speaking African countries (PALOP) and East Timor.
Doses have already been sent to Cape Verde, Guinea-Bissau, Mozambique and Sao Tome and Principe.
East Timor should receive the first 12,000 vaccines offered by Portugal next week.
Angola has counted 40,327 cases of Covid-19 since the pandemic began, including 946 deaths and 34,584 recovered cases, with 4,797 cases now active.
According to the latest figures from the African Union's Centre for Disease Control and Prevention, the continent has now surpassed six million cases and is immersed in an aggressive third wave of the disease.