The couple began dating in 2008 after being introduced by Blunt's Devil Wears Prada co-star Anne Hathaway and eventually married last summer in Italy.
During an interview on The Ellen DeGeneres Show, Krasinski admitted that his immediate attraction to his future spouse took him by complete surprise.
"It's one of those things where as soon as you meet someone, you [know you're in love]," Krasinski revealed.
He went on to say: "I wasn't really looking for a relationship and I was thinking I'd take my time in LA and everything. Then I met [Emily]. I was so nervous, [thinking] 'Oh God, I think I'm going to fall in love with her'. As I shook her hand, I went, [grunting] 'I like you!' So if anybody's looking [into] how to pick up a girl, that's the way you do it!"
Earlier this week, Krasinski disclosed that he doesn't know who will replace Steve Carell's character Michael Scott as the boss of The Office, which airs tonight at 9pm ET/8pm CT on NBC.
> John Krasinski: 'Blunt understands me'
Watch John Krasinski discuss his feelings for Emily Blunt below: