The Keeping Up With The Kardashians star, 35, announced the birth of her and Kanye's second child on 5 December, but hasn't shown us any full pictures of him on social media - until now.
It was worth the wait, he's a total cutie!
Saint can be seen dressed in white and is sound asleep with his arms up in the air.
Kim shared the heartfelt reason behind her decision to share the first photo of her baby, explaining it was to mark late father Robert Kardashian's birthday.
She wrote on her personal website: "Today is my dad's birthday. I know there's nothing more in the world he would have wanted than to meet his grandchildren. So I wanted to share this pic of Saint with you all."
Kim first announced the birth of Saint in a statement on the website, telling fans: "Kanye and I welcome our baby boy!"
It added: "Kim Kardashian West and Kanye West welcomed the arrival of their son this morning. Mother and son are doing well."
Kim and Kanye are already parents to North, two, who was born in June 2013. The couple waited two months before unveiling the first photo, which was shown on Kris Jenner's US chat show.
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