The dinner was also a family affair, as he was accompanied by his eldest son Mason, 13, his daughter Penelope, 11, and his youngest son Reign, eight, all of whom he shares with his 44-year-old ex.
Mason donned baggy jeans and a black T-shirt, while Penelope wore gray sweatpants with a brown sweatshirt and Reign rocked a brown velour sweatsuit.
The Kourtney lookalike wore an off-the-shoulder black sweater and black pants with her familiar black bob hairstyle.
The outing to the high-end Japanese restaurant comes after Kourtney gave birth to her first child with husband Travis Barker, 48.
Type: Scott Disick definitely has a type. The Talentless founder, 40 stepped out for dinner at Nobu in Malibu
The dinner is a rare public appearance by Mason who prefers to stay out of his famous family’s limelight.
Mom Kourtney told the Not Skinny But Not Fat podcast that her teenager ‘craves’ a sense of normalcy.
‘He doesn’t want any part of it. He’s not on social media,’ his mom said last year.
In addition to Mason, Disick is dad to Penelope, 11, and Reign, eight, with the eldest Kardashian Jenner sister.
Mason became a big brother again last month when his mom and stepdad welcomed son Rocky Thirteen Barker.
As for how Disick is feeling about his ex having her fourth child, a source told Entertainment Tonight that he was ‘being as supportive as possible while also trying to take care of himself.
‘It stings a little and he will always have love for Kourtney, but at the same time he is also happy and excited for her,’ the source continued.
‘He wants to continue to move on and focus on his own personal life.’
Sushi dinner: He was accompanied by his sons Mason, 13; and Reign, eight; along with daughter Penelope, 11; and a woman who is a doppelganger for his ex-girlfriend Kourtney Kardashian, 44
Celeb hot spot: The Kourtney look-a-like wore an off-the-shoulder black sweater and black pants with her familiar black bob hairstyle
Father and son: Mason donned baggy jeans and a black T-shirt, while Penelope wore gray sweatpants with a brown sweatshirt and Reign rocked a brown velour sweatsuit
New member of family: The outing to the high-end sushi spot comes after Kourtney gave birth to her first child with husband Travis Barker, 48
Rare appearance: The dinner is a rare public appearance by Mason who prefers to stay out of his famous family’s limelight
Last week, Kourtney made her first statement since Rocky was born to wish Travis a happy birthday.
Kourtney wrote: ‘To my husband, my soulmate, my best friend, my lover, my daddy to our baby boy, my everything…
‘I wish you the happiest birthday. You make all of my dreams come true and I feel so blessed to have you by my side. I love you beyond words, forever.’
The new dad was spotted at his studio in Los Angeles on his birthday with his friend, Limp Bizkit frontman Fred Durst, 53.