Lying along the ancient Via Aurelia, the Roman Monilia was a strategic centre in that age. In 774 Charlemagne donated the village and its territory to Saint Colombanus Abbey in Bobbio that developed the trades between the sea and the Po Valley.
Under the jurisdiction of the Republic of Genoa, Moneglia took part to the successful Battle of Meloria against Pisa, in 1284.
During the World War II Moneglia was bombed by the Allies that tried to destroy the railway bridge, between the village and the beach.
The former railway tunnels, now the main road to reach Sestri Levante by car, represented a safe shelter for the inhabitants.