According to E!, the Guardians of the Galaxy star is "thrilled" to be expecting two babies with her husband, who she's been married to for over a year.
Us Weekly also reported that Zoe is about three months pregnant, but don't expect a funny announcement tweet from her just yet.
"She will only announce the news when she's ready," their source reported.
She is a busy actress, after all! Zoe was just seen on the red carpet to promote Guardians on Monday, but remained tight-lipped on her twin news. Instead, she let her growing bump do all the talking, in a belted print dress.
"Zoe has always wanted a big family," the outlet reports. "And Marco's on board too!"
How did you react when you found out you were having twins?