Valentine's Day is a day observed by both humans and Smurfs alike. It is usually a time when Cupid the ambassador of love comes out to shoot his love arrows at creatures and living beings so that they can feel and express love toward one another. It is also when valentines are created for loved ones. Valentine's Day is considered a Christian day of observance that was founded from the Christian saint Valentine who was a martyr.
In the cartoon show special "My Smurfy Valentine", which takes place on Valentine's Day, Smurfette was wishing to create one big valentine for her Prince Smurfing to come and so she wrote a letter to Cupid in the hopes that he would grant her heart's desire. However, Gargamel took advantage of the letter when he intercepted it and lured Smurfette into a trap by writing her a letter that came from her "Prince Smurfing", telling her to meet him by the Great Oak Tree. Also on that day, the evil witch Chlorhydris was looking for a suitable cat that would grant her access to a hidden wishing well that had power to grant a single wish once every 1000 years on a Valentine's Day that had a solar eclipse. With nowhere else to turn to, Chlorhydris offered Gargamel gold for his cat Azrael but deceived him and locked him away in her castle with her captured cats while she took the cat to the magic wishing well. Overhearing about the wishing well, Smurfette planned to get there before Chlorhydris in order to have her wish of a Prince Smurfing granted, but she got stuck in the Forest of Poison Thorns until Cupid came to her rescue, telling her the best place she can find true love is in her heart. Gargamel also made his way to the wishing well in order to stop Chlorhydris from making her wish, but when the Smurfs got there with Cupid, he fired his arrows at both Gargamel and Chlorhydris, causing them to fall in love with each other. Smurfette was about to make her wish when she sees Azrael approach the well to attack Papa Smurf, so she instead makes her wish to have everyone go back to where they belonged -- and at that instant, the Smurfs returned to their village, Chlorhydris returned to her castle stuck with her cats, and Gargamel returned to his home with Azrael stuck in his own trap. While Clumsy expressed his disappointment that Smurfette didn't find her Prince Smurfing, Smurfette told him that she had found her Prince Smurfing in the hearts of her fellow Smurfs.
In the 2021 TV series episode "Gargamel Goes Gaga", a valentine's day party was being hosted and is seen at the beginning and end of the episode. The Smurfs are seen organizing decorations for the special day.