About 1000 people attended the Mass in Holy Cross Cathedral, including Solomon Islands Prime Minister Manasseh Sogavare, Governor-General Frank Kabui, New Zealand High Commissioner Don Higgins, the United States and Japanese ambassadors, and high commissioners from Australia and the United Kingdom.
The Catholic Archbishop of Honiara, the Most Rev Christopher Cardone, led the service, saying: "We come together in celebration of a battle that changed the world".
The bitter six-month battle for the main Solomon Island of Guadalcanal and its Henderson Airfield in 1942-43 was crucial to the Allies in the campaign to push back the Japanese and prevent them isolating Australia and New Zealand.
The Solomon Islanders were caught between two major powers and they suffered, too, Archbishop Cardone said.
The name Guadalcanal was an emotional one, yet it was unknown until the battle "in which so many fought and died", he said.
It was estimated that 25,000 Japanese and 1600 Americans and Allied soldiers died on Guadalcanal. Many aircraft were downed over the island and 48 ships sunk in the waters around Guadalcanal, including HMS Moa in April 1943 with the loss of five lives.
"We remember all the men who served here in the Solomon Islands and all who died for their countries thousands of miles from home," the archbishop said.
"We come here today because we want peace," he said.
