The two men and two boys -- part of a cluster of six new confirmed cases -- were released from the ELWA II clinic in Monrovia after making a full recovery.
"This is a clear indication that we are capable of facing the outbreak whenever there is one," deputy health minister Tolbert Nyensuah told reporters at the treatment unit.
"Our doctors were able to stop the virus from killing these people. Today they are free and will be given the certificate (of recovery)."
But a 17-year-old died in the coastal county of Margibi at the end of June after passing the virus on to five others, one of whom died.
Also Read
The recovered patients, aged nine to 24, came from the same village as the first of the new cases, near the country's international airport and about an hour's drive southeast from Monrovia.
Othelo Miah, 19, said he was among a group of villagers who had eaten cooked dog flesh with the 17-year-old -- originally and incorrectly attributed as a possible source of the new outbreak.
ELWA 2 said four people who were thought to have had contact with the patients had also been released, having escaped infection, while six remained under observation.
Scientists believe the resurgence of Ebola is likely to have originated in a survivor still carrying the virus.
Ebola has infected 27,700 people and killed almost 11,300 across Liberia and its neighbours Guinea and Sierra Leone, according to official data widely thought to underestimate the toll.
There were 30 confirmed Ebola cases reported in the week to June 12, according to the WHO -- 13 in Guinea, three in Liberia and 14 in Sierra Leone.