The McCook Family Estate (also known as the Willis McCook House) located at 5105 Fifth Avenue in the Shadyside neighborhood of Pittsburgh, Pennsylvania, USA, was built in 1906 and 1907 for Willis McCook and his family. McCook was a lawyer who represented Henry Clay Frick. The house has been renovated and converted into a bed and breakfast inn called the Mansions On Fifth Hotel. The house was added to the List of Pittsburgh History and Landmarks Foundation Historic Landmarks in 2009, and to the National Register of Historic Places on April 20, 2011.