Some ports of entry including Roberts International Airport will remain open, but incoming and outgoing passengers will be subject to inspection and testing for the disease.
Nigerian airline, Arik Air, has suspended flights to and from Liberia and Sierra Leone after a Liberian man died of Ebola after he arrived at Lagos airport on July 22.
For those "communities that are seriously affected," President Ellen Johnson Sirleaf announced, they "will be quarantined and travels in an out of such communities restricted."
The decision to close most of Liberia's ports of entry and quarantine infected areas comes as the Liberian president declared the Ebola virus a national emergency on Sunday and announced the establishment of a national task force to combat the spread of Ebola.
"Our task is to work with the health team and provide support and guidance to them. We also will be establishing a community outreach force with individuals mobilized to reach out to communities to sensitize them to the disease, to provide them information as to how they can protect themselves."
The Ebola outbreak has claimed the lives of 127 Liberians and infected 224 others, according to World Health Organization statistics.
Liberia is among three West African nations most affected by the Ebola outbreak. Guinea and Sierra Leone are also grappling with the deadly virus.
As of July 20, WHO reported a total of 660 deaths and 1,093 cases from confirmed, probable and suspected Ebola in Guinea, Liberia and Sierra Leone.