The bill, introduced in parliament last month, was passed by the country's National Assembly despite calls from the opposition and civil society for wider consultations.
It will see the introduction of a vice presidency position while increasing the number of seats in the National Assembly from the current 72 to 96 and in the National Council, an upper house of Parliament, from 26 to 42.
Other notable changes include the increase of presidential appointments to the National Assembly from six to eight, and the creation of the Namibia Central Intelligence Service whose head will now be appointed by the president.
Opposition parties and civil society had urged the ruling party to defer debate on the new constitutional changes claiming that they were not consulted before the bill was rushed through parliament.
They also claimed that the new changes ahead of the country's presidential and parliamentary elections set for November are meant to appease the ruling party Swapo's old guard who would otherwise not have made it into parliament after the party resolved to introduce a 50:50 gender quota in all its structures.
The bill is now set to be rubber stamped by the National Council.