'Shark Tank' Star Robert Herjavec Buys Hidden Hills Home

Robert Herjavec is expanding his real estate portfolio ... TMZ has learned the "Shark Tank" star just picked up a beautiful, massive pad outside L.A. and in Kim Kardashian's backyard.

Sources familiar with the deal tell TMZ ... Robert just snatched up a recently renovated home in Hidden Hills. We're told he paid close to the asking price of $15.5 million.

The place is pretty sick ... the estate sits on 1.7 acres and the 13,000-square-foot home has a whopping 7 bedrooms and 9 baths -- plenty of space for Robert and his wife, 'DWTS' alum Kym Johnson and their 1-year-old twins.

It's also loaded with tons of lavish amenities ... we're talking pool, tennis court, playground, gym and a home theater. The sweeping property also features trails for hiking and riding horses -- and a guest house ... y'know, for the in-law visits.