The 34-year-old actress, who has been dating David since June 2018, revealed the happy news to her followers on Instagram, as she showed off her stunning engagement ring.
Alongside the snap of herself with David and their pet bulldog, Jenna wrote: "Yes, a million times, yes."
Stanley shared the same image on his Instagram page and wrote, "Yes", alongside several heart emojis.
The pair quickly received messages of congratulations from their famous friends, including Sarah Hyland who commented on the picture: HOLY S**T!!!! YES!!!!! IT'S F**KING GORGEOUS."
Meanwhile, actress Ally Maki wrote, "YES YES YESSSSSSSSSSSS... still screaming!!!"
The happy news comes after a difficult few weeks for Jenna, following the tragic death of her former "Glee" co-star Naya Rivera. After Naya drowned in a freak boating accident on Lake Piru, Jenna penned a heartfelt tribute to her late friend.
"Naya, you were a force and everyone who got to be around you knew it and felt the light and joy you exuded when you walked into a room," she wrote. "You shined on stage and screen and radiated with love behind closed doors... I can not believe I took for granted that you'd always be here."