A group of missionaries from the Presbyterian Church in the USA (Synod of New Jersey) established itself on the island of Corisco in the Gulf of Guinea in 1850, after having worked in Liberia and Gabon. From there they moved to the mainland where they founded the first congregation in Bolondo (now Mbini). They spread into the interior of the continent setting up more congregations, as they did also in the coastal area. The presbytery of Rio Muni celebrated its centennial in 1960. In 1900 France yielded the territory of Rio Muni to Spain. This resulted in the establishment of the Roman Catholic Church, marked by an attitude of inquisition. Intolerance and persecution produced an unavoidable change in the circumstances of the church which had to give up its schools and medical work. In 1924 all the missionaries were obliged to leave the country.

In order to revitalize the work, the American Presbyterian Mission sent a missionary couple in 1932 who prepared young people for the seminary and organized the dynamic Women’s Association, which up until today remains the life and soul of the church. There came a time of revival with the establishment of the Republic in Spain, which continued until the outbreak of the Spanish civil war in 1936. During this period the Youth Association was set up.

In 1952 the Spanish government, which was close to the Catholic hierarchy, closed all the Protestant churches, allowing only those which existed before the establishment of the Franco regime to re-open. In 1957 the presbytery of Rio Muni joined the Presbyterian Church of Cameroon as part of the MUNICAM synod. A year later it withdrew for reasons which had to do with the process of decolonization, and integrated the Synod of New Jersey (USA). Several American missionaries worked in the church during this period, but left in 1968 shortly before independence. Between 1936 and 1962 the church was strengthened by the activities of a number of pastors sent by the Presbyterian Church of Cameroon.

In 1960 about twenty delegates met for the last time as the presbytery of the Synod of New Jersey. They approved a new constitution and the church became autonomous as the Evangelical Church of Equatorial Guinea. The independence of the country on 12 October, 1968, brought with it religious freedom, legalized and guaranteed by the state which is secular. Today this ecclesiastical community, which labours with total freedom, defines itself as the Reformed Presbyterian Church of Equatorial Guinea. It is Reformed by its theology and Presbyterian by its form of government, as stated in its constitution.