Originally built in 1869, the McCoy House is the reconstructed wood-frame residence of Sheriff James McCoy and his wife Winnifred. McCoy came to San Diego in 1849 after serving in the U.S. Army. Fluent in Spanish, this Irish-born immigrant served as county assessor in 1859, city sheriff for ten years, and as a state senator in 1871. McCoy built the house as a wedding present and made sure to include plenty of amenities befitting his station in the community. The house had shutters on either side of the numerous windows, a white picket fence, and shrubs and trees to shade anyone who rested on the large front porch. The Greek Revival architectural style of the large, two-story home with a columned front porch was popular among many wealthy 19th century Americans.

In March 2000, the California Department of Parks and Recreation completed construction of the Old Town San Diego State Historic Park Entry Redevelopment project, which included extensive landscaping and reconstruction of the McCoy House. State Park archaeologists excavated in Old Town San Diego in 1995 to recover information needed to reconstruct a large residence built in 1869 by James McCoy, a well-to-do Irish immigrant who served as San Diego's sheriff and state senator. Prior to 1851, the property belonged to Alta California in the 1770s. A portion of the archaeological findings have been preserved and interpreted as part of a series of interpretive displays on the park and its history within the house itself.