The baby boy was born aboard a Medecins Sans Frontieres (MSF) refugee and migrant rescue vessel operating in the Mediterranean on Monday morning.
His mother Faith was "already having contractions when she left Libya and was terrified she'd give birth on the rubber boat," said MSF in a tweet.
It was a "very normal birth in dangerously abnormal conditions," added the charity's midwife, Jonquil Nicholl.
The boy's dramatic entry into the world comes after around 2,300 migrants were rescued in 18 sea missions on Sunday, according to the Italian Coast Guard.
Vessels belonging to the Irish navy, MSF and Save the Children all took part in the operation coordinated by the Coast Guard in Rome.
Life goes on
Monday's birth follows last month's rescue of five-day-old twins
, who were among 6,500 refugees saved while attempting to make the treacherous journey across the Mediterranean.
Their mother, 26-year-old Merhawit Tesfamariam from Eritrea, gave birth to the boys on board a rickety boat off the Libyan coast in late August.
After being rescued by MSF, her premature twins Hiyap and Evenezer were treated at Palermo's Cervello Hospital in Sicily.
Migrants flee conflict and violence
This year, 264,513 people arrived in Europe by sea
, landing mostly in Greece and Italy, according to International Organization of Migration (IOM) estimates released in mid-August.
Of those who attempted the crossing, 3,165 people have died at sea, authorities said. At this rate, according to the IOM, the number of deaths will likely exceed last year's total of 3,771.
Most of the deaths in 2016 came from people risking the Libya to Italy route, which is considered dramatically more dangerous. They're also using flimsy plastic rafts or wooden crafts not built for such a voyage, and all of the vessels tend to be overcrowded -- some carrying 600 or more passengers, according to the UN Refugee Agency.