Prince Nicolas Paul Gustaf, also set to be known as the Duke of Ångermanland after a province in northern Sweden, is the first grandson of King Carl XVI Gustaf, who has two granddaughters.
Around 150 guests, mostly family and friends, attended the ceremony in the church of Drottingholm Palace, just outside Stockholm.
Nicolas is sixth in line to the Swedish throne after his sister, Princess Leonore. Their mother is fourth.
Nicolas, who was born on June 15th, was dressed in the same christening robe that his older sister wore at her baptism last year.
Princess Madeleine and Christopher O'Neill with Nicolas greet the waiting crowds after the ceremony. Photo: TT
Princess Leonore nearly grabbed the headlines herself by toddling too close to the baptism font.
Following the service, his mother and father took Nicolas to greet well-wishers who had waited outside in the sunny weather during the event.
Sweden is a constitutional monarchy in which the royals primarily serve as figureheads. The king is the country's head of state, but his powers are limited to ceremonial duties.