Mission Puerto de Purísima Concepción, Spanish colonial mission in Yuma, Arizona, United States.

Mission Puerto de Purísima Concepción was founded in October 1780 by the Franciscan Francisco Garcés near present-day Yuma, on the California side of the Colorado River. Nothing of the mission or its pueblo remains; the site is identified only by a historical marker on Picacho Road in Fort Yuma, California, one mile south of Winterhaven Road.

Franciscan missionary Francisco Garcés founded Mission Puerto de Purísima Concepción in October 1780 on the California side of the Colorado River near present-day Yuma. It was not part of the California mission chain but was administered within the Spanish missions in Arizona. Spanish colonists seized the best lands and destroyed Quechan crops, and on July 17–19, 1781, the Quechan and their allies destroyed the mission and nearby Mission San Pedro y San Pablo de Bicuñer.

The site is now marked only by California Historical Landmark No. 350, a plaque on Picacho Road in Fort Yuma, California, one mile south of Winterhaven Road. The marker recalls the October 1780 founding by Father Francisco Garcés and the Quechan and allied attack of July 17–19, 1781, which destroyed the mission and the nearby Mission San Pedro y San Pablo de Bicuñer.

The historical marker is located on Picacho Road in Fort Yuma, about a mile south of Winterhaven Road, and is accessible by vehicle. Visitors should note that the location is remote and it is wise to check local conditions before traveling to the site.

The settlement was destroyed in July 1781, just nine months after its founding, making it one of the shortest-lived Spanish colonial efforts in the region. This rapid end shows the deep conflicts between colonial ambitions and the local resistance they encountered.