Having tweeted earlier in the morning about Italy's December 4th referendum, Salvini shared an image of himself with the Republican shortly after American media confirmed that Trump's rival Hillary Clinton had conceded the election.
"Good morning!" read the cheery slogan on the image, which was accompanied by the hashtags '#godonaldgo' and '#oratoccaanoi# (now it's our turn).
The picture showed Salvini with Trump, in colour, beside a faded grayscale image of outgoing US President Barack Obama with Italian PM Matteo Renzi. His Tweet included the hashtag '#iovotono' 'I'm voting no', referring to Italy's upcoming referendum on constitutional reforms.
At 9am, neither Renzi nor Foreign Minister Paolo Gentiloni had made a public statement on Trump's election.
During the election, Salvini had described Trump as "heroic" and said he would like to meet the TV celebrity and shake his hand. He added that he felt they were "on the same wavelength" about many issues.
After meeting at one of Trump's rallies - the event where the photograph in the Tweet was taken - the American later snubbed Salvini, saying the pair had never met, but the Northern League leader continued to share his support for Trump via social media.
In France, the leader of the anti-immigration Front National, Marine Le Pen, was also quick to share her congratulations with the billionaire businessman.
Trump's unexpected victory will give right-wing parties in Europe added confidence in their efforts to upset the 'establishment' in their own countries.