Reese was flashing the most beautiful smile in a perfect white bridal dress, while her new husband kissed her on the side of the head.
Alongside the adorable picture, the Legally Blonde star left the most heartfelt message for her husband of ten years.
WATCH: Reese Witherspoon's children make rare appearance in fun video
"Celebrating 10 years of marriage to my sweet hubby," she wrote. "What a special day with all of our dear friends.
"Looking back, I can't believe it has gone so quickly! I guess that's how it goes with 3 kids, Big LOVE, lots of laughing, non-stop travel, so many dogs, and fun adventures… figuring out this crazy world together."
She finished her message by adding: "Here's to many more days in the sun! I [heart emoji] you, JT!"
She also uploaded a series of Instagram stories charting the couple's love story, featuring them meeting eleven years ago, their wedding day, and a current-day snap of them on the beach.
The couple celebrated their tenth anniversary
Fans went wild for the sweet post and paid their own tributes to the happy couple. "Happy day to the most beautiful hearts," wrote one, while another fan added: "Happy anniversary!! Love you two so much!"
A different commenter wrote: "Your smile is so beautiful," while a fourth added: "Happy anniversary! Love seeing you both so happy. Wishing you all the best and congrats!"
Reese shared a current-day photo of the couple
Reese and Jim share one child together, son Tennessee James Toth, aged eight.
The star also has two other children from her marriage to her Cruel Intentions co-star, Ryan Phillippe, daughter Ava Elizabeth Phillippe, 21, and son Deacon Reese Phillippe, 17.
And Reese's two sons recently made an appearance in a video she shot in a 'day in the life of' style.
The footage showed Reese having fun dancing in the living room with her youngest child as they played Just Dance, while Deacon relaxed in the living room with the family's pet dog.
The Little Fires Everywhere star loves nothing more than being a mum, and previously told Glamour magazine that her children are always on her mind.
"I don't think there's been an hour of my life since Ava was born that I don't think of my kids," she said. "I call it my CNN ticker tape: Is Ava OK? Yes. Is Deacon OK? Yes. Is Tennessee OK? Yes. Back to Ava."
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