The "Big Bang Theory" actress was spotted wearing a diamond ring on a Los Angeles film set, which sparked rumors that the two were getting hitched.
Cuoco, 27, is currently shooting the film "The Wedding Ringer," which made some think that the sparkler could be a movie prop, not her real-life engagement ring.
The blonde began dating tennis star Sweeting earlier this summer, and the couple made their first red carpet appearance Sunday at the 2013 Primetime Emmy Awards.
Since then, the pair have been inseparable, being spotted at the U.S. Open and getting mani-pedis together. Sweeting proposed early Thursday, and the two have been firing off giddy tweets nearly nonstop since.
Flying high, I could literally touch the sky with you....— Kaley Cuoco (@KaleyCuoco) September 25, 2013