The Convent of the Sacred Heart is a Roman Catholic all-girl school in the Manhattan borough of New York City and the oldest private school in the city.

Founded in 1881 by the Society of the Sacred Heart, a Roman Catholic congregation established in France in 1800, the school is New York City’s oldest private school for girls. The school was originally housed in a Manhattan brownstone on Madison Avenue at East 54th Street. By the 1930s, the school had outgrown its Madison Avenue space and moved to its current location.

The school is housed in the former Otto H. Kahn House and James A. Burden House, both of which are New York City-Designated Landmarks.

Otto Kahn, a senior partner at the investment bank, Kuhn, Loeb and Co. commissioned architects J. Armstrong Stenhouse and C.P.H. Gilbert to build his home in the neo-Italian renaissance style. The mansion was modeled after the palazzo della Cancelleria of the Papal Chancellery in Rome. It took four years to construct the mansion. The mansion includes an indoor courtyard, garden, and private driveway.

Kahn housed an extensive art collection inside the mansion, including tapestries, glass chandeliers, and valuable paintings by Boticelli. Enrico Caruso and George Gershwin were among the Kahn's many famous friends, who were often known to give impromptu performances at the mansion. Following Kahn's death in 1934, the house was sold to the Convent of the Sacred Heart.

The adjoining James A. Burden House was commissioned by William D. Sloane as a wedding present for his daughter Adele, who married James A. Burden II, heir to the Burden Iron Works.

Completed in 1905, the home is an Italian Renaissance-style townhouse, embellished by French-inspired detailing around the windows and balcony. A Designated Landmark of New York plaque was installed by the New York Landmarks Preservation Foundation in 1989.