"This is a very personal decision, and I've decided to take 2 months of paternity leave when our daughter arrives," he said in the post. "Studies show that when working parents take time to be with their newborns, outcomes are better for the children and families."
He said: "At Facebook we offer our US employees up to 4 months of paid maternity or paternity leave which they can take throughout the year."
Zuckerberg announced in July that his wife, Priscilla, was expecting a baby girl, following three miscarriages.
Zuckerberg added in Friday's post, "Every day things are getting a little more real for us, and we're excited to start this next stage in our lives."
Sheryl Sandberg, Facebook’s COO and author of "Lean In," offered her congratulations in a comment on Friday's post, writing, "Mark and Priscilla, I'm so excited for both of you. Enjoy the precious early months with your daughter -- I can't wait to meet her."
Facebook isn't the only company to offer paternity leave.
Microsoft said in August it would offer paid parental leave of 12 weeks, "paid at 100 percent, for all mothers and fathers of new children," starting Nov. 1. Microsoft executive vice president of human resources Kathleen Hogan said, "For birth mothers, this is in addition to the eight weeks of maternity disability leave they currently receive, paid at 100 percent, enabling them to now take a total of 20 weeks of fully paid leave if they choose."
Netflix also announced in August a new policy of "unlimited" maternity and paternity leave. The video-streaming company's policy allows moms and dads to take as much time as they want -– with pay -- during the first year after a child's birth or adoption.