The 73-year recently took to Instagram to show off his new look, reports dailymail.co.uk.
In the clip, the Oscar-nominated actor is seen chatting in the back of his car as he pumps his fist and says: "Keep punching, my friend. Keep punching."
Alongside the clip, the actor shared a motivational post that read: "Sometimes I wake up I feel like doing nothing. Just relaxing. Just very true. If anyone says different, they're lying - it's human nature."
"Then you roll over, get a little mad at yourself, and realize to get anywhere you've got to make a deposit in the GOAL BANK. So, I'll go back to my favourite phrase and do it!! #KeepPunching."
Fans were quick to comment on his new look. One wrote: "Aren't easy to live this long with the fame and power. Proud of you with the silver hair." Another wrote: "Woah sly you look amazing".
Other comments read: "Stay grey my friend, Stay grey #staygold"; "You look Greyt champ"; "Stay true to the gray!! Looks good on ya!"; "Loving the gray".
Over the past few weeks, Stallone has been pictured sporting a salt and pepper look, but now he has allowed his previously dyed black hair to grow out.
( With inputs from IANS )