Emperor Naruhito and Empress Masako waved and smiled from an open vehicle in Sunday's motorcade which passed through central Tokyo, marking his enthronement before about 120,000 delighted well-wishers who cheered, waved small flags and took photos from both sides of packed sidewalks.
The 4.6 km parade route took the emperor and empress from the Imperial Palace to the Akasaka Estate.
The parade was supposed to take place on the day of the announcement of the accession of the new emperor to the throne on October 22, but due to the tragic consequences of the typhoon Hagibis, which shortly before that claimed the lives of 95 people, it was chose to transfer him to this Sunday.
The couple's first parade since their marriage in 1993 was originally scheduled for October 22 as part of a series of events marking the official proclamation of Emperor Naruhito's enthronement.
There are expectations that Naruhito, the first emperor with a college degree who also studied overseas, and his Harvard-educated wife Masako, will internationalise the imperial household.
Tight security will be in place, with police conducting ID checks at buildings along with the route and baggage inspections at dozens of locations from the morning.
The motorcadewas led by a black Century limousine from Toyota Motor.
Emperor Naruhito expressed gratitude to about 30,000 well-wishers who gathered at the entrance of Imperial Palace in Tokyo on November 9 in a festive event celebrating his accession to the throne.
Akihito's abdication this year brought Naruhito to the throne and marked the start of the Reiwa era. Some experts say the government's funding of the Shinto harvest ritual could violate constitutional separation of state and religion.
People had already gathered around the Imperial Palace in the morning so they can get a good look at the Imperial couple.
Yoko Mori, 64, lined up from 10: 00 am to secure a spot, travelling from Saitama outside Tokyo.
"The sky is so blue and this is a great day for taking photos, as if it's the heaven's blessing for (the emperor)", said Suzuki, an amateur photographer.
He said he admired the former emperor and wants to see Naruhito continue his father's work.
"Emotion welled up and I was so happy that I was about to cry", she said. Conservatives insist on the male-only succession, but Suzuki says he wouldn't mind a female monarch.
The Rolls-Royce that carried Akihito in 1990 was retired in 2007. Many Japanese were especially impressed by the couple freely conversing with President Donald Trump and first lady Melania Trump during their visit weeks after Naruhito's succession in May, according to palace watchers.
"I'm looking forward to see the dress Empress Masako will wear", Ms Hiroko Kikuta, in her 60s, told AFP.