Steph turned the big 3-4 on Monday ... and Ayesha was there to congratulate her husband on another year of life.

"Happy birthday to the love of my life!," Ayesha said on Instagram. "You bring our family so much joy and happiness. We love you beyond measure. The year ahead is bright and I can’t wait to watch you grow and thrive even more."

"To my favorite person in the world, happy birthday @stephencurry30 ! 🥰🥰🥰."

Steph and Ayesha first met when they were in high school. After years of dating, Steph proposed to Ayesha ... and the two tied the knot in 2011. The power couple has been married for more than 10 years and now have three children together -- Riley Elizabeth, 9, Ryan Carson, 6, and Canon W. Jack, 3.

Of course, Steph's wife doesn't mess around when it comes to their union -- she recently denied rumors alleging they were in an open relationship ... saying the claims are "ridiculous" and calling it disrespectful to her marriage to make such an insinuation.

Ayesha is by far Steph's biggest cheerleader -- she was in the building at Madison Square Garden when Steph passed Ray Allen for the most 3-pointers made in NBA history.

It's clear their love is going stronger than ever!!