The Oregon Pioneer Association (originally known as the Oregon Pioneer Society), first established in October 1867, was a fraternal and lineage society and historical organization for early American settlers of the Oregon Territory.
The Association, a non-governmental organization, had both fraternal and academic aspects. Its members gathered at conventions and published annual addresses dealing with pioneer life. The group thrived throughout the decades of the 1870s and 1880s, eventually giving way due to the attrition of its members to a new organization known as the Sons and Daughters of Oregon Pioneers, established in 1901. The OPA appears to have terminated in approximately 1928.