Ogna is a former municipality in Rogaland county, Norway. The municipality existed from 1839 until its dissolution in 1964. The municipality encompassed roughly the southern third of the present-day municipality of Hå. The administrative centre of the municipality was the village of Ogna where the Ogna Church is located. The municipality of Ogna was established in 1839 when it was split off from the (much larger) municipality of Egersund landdistrikt, the rural municipality surrounding the town of Egersund. Initially, there were 825 residents of Ogna. During the 1960s, there were many major municipal changes across Norway due to the work of the Schei Committee. On 1 January 1964, the three neighboring municipalities of Nærbø, Varhaug, and Ogna were all merged into one large municipality called Hå. Prior to the merger, Ogna municipality had 1,470 residents. The municipality (originally the parish) is named after the old Ogna farm (Ógna) since the first Ogna Church was built there. The name comes from the verb ógna which means "to threaten", likly referring to the local river since it has strong currents and it is prone to flooding in the spring. Historically, the name was spelled Ogne. While it existed, this municipality was responsible for primary education (through 10th grade), outpatient health services, senior citizen services, unemployment, social services, zoning, economic development, and municipal roads. During its existence, this municipality was governed by a municipal council of directly elected representatives. The mayor was indirectly elected by a vote of the municipal council. The municipal council (Herredsstyre) of Ogna was made up of 15 representatives that were elected to four year terms.