The 70-year-old actor and 65-year-old actress marked the occasion Sunday by enjoying an early morning walk together.
Steenburgen shared a photo from the outing on Instagram. She dedicated a sweet message to Danson in the caption.
"Early morning walk celebrating our wedding October 7, 1995! That's 23 years or 714 in actor's years :) #hereallyisasgreatasyouthinkheis," the star wrote.
Danson and Steenburgen met on the set of the 1994 film Pontiac Moon. The couple discussed their longtime romance in an interview with Closer Weekly published in July.
"I'm ridiculously in love with him," Steenburgen gushed. "I find him endlessly fascinating. He surprises me all the time and most of all, he makes me laugh."
"I get nervous around her because I want to impress her," Danson said. "I am the luckiest. When I die, I will have known in this life what it is to love as a human being and to be loved, and I am so grateful."
Danson is known for playing Sam Malone on Cheers, and presently stars on the NBC series The Good Place. Steenburgen most recently appeared in the movie Book Club with Diane Keaton.
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Longest celebrity relationships