The architecture firm has not revealed how high the tower will be, but it is expected to exceed 96 metres – the height of the Hungarian Parliament Building and Saint Stephen's Basilica.
The campus is intended to be a model of sustainability, including responsive lighting, heating and ventilation systems; low-carbon energy sources such as photovoltaic panels; and rainwater harvesting and storage facilities.
The scheme also includes large areas of greenery, state-of-the-art workplace facilities, cycling infrastructure and a public "skygarden". Foster + Partners describes it as "a vision for the workplace of the future"
"This is a landmark project for several reasons, not only for MOL but also for Budapest," said Nigel Dancey, who is head of studio for the London-based firm.
"It presents a unique challenge – to ensure that the building meets the functional needs of the organisation, follows the highest standards of sustainability, and is respectful of its historic surroundings."
The tower is designed to rise up out of a podium building, and the two will be united by a curving glass facade.
Inside, offices will be interspersed with outdoor patios and gardens, so that employees can regularly interact with nature. Meanwhile the skygarden at the top of the building will be accessible to the public.
"As we see the nature of the workplace changing to a more collaborative vision, we have combined two buildings – a tower and a podium – into a singular form, bound by nature," added Dancey.
"As the tower and the podium start to become one element, there is a sense of connectivity throughout the office spaces, with garden spaces linking each of the floors together."
Led by architect Norman Foster, Foster + Partners is now one of the world's biggest architectural practices. The studio, which ranked at number 13 on Dezeen Hot List 2016, has also recently unveiled large development plans for Stockholm, Sydney and Brooklyn.
The firm's recently completed projects include a Shanghai theatre with a curtain-like facade, which was designed in collaboration with Heatherwick Studio.