Heidi Baker (born 1959) is a christian missionary and with her husband Rolland co-founder of IRIS Ministries and the author of several books.

With her husband Rolland, Heidi founded IRIS Ministries in 1980,^[1] a non-profit christian ministry dedicated to Jesus and service, especially among the poor. After twelve years ministering in Asia, they left in 1992 to do their PhD's at King's College London, UK. In 1995 they started a new ministry to the poor and homeless children in Mozambique. Beginning with nothing, within a matter of months they were given a dilapidated orphanage in Maputo with 80 children. From there, the ministry has expanded to include well-drilling, free health clinics that service the poor and sick, feeding programs, primary and secondary schools, cottage industries and 5000 churches in Mozambique and a total of over 8,000 churches in over 20 nations. There are multiple 'bases' with Bible schools, as well as community outreaches and top-ranked public schools. In September 2008 Iris Ministries started a well digging project in Northern Mozambique. Their ministry is known for its reports of miracles, and in September 2010 the Southern Medical Journal published an article presenting evidence of "significant improvements" in auditory and visual function among subjects exhibiting impairment before receiving prayer from the ministry.

Originally from Southern California, the Bakers are now based full-time in Pemba, Mozambique. They also travel to various places around the world to share their story, and to teach about God's love and what love in action looks like. The core value and message of the Bakers ministry is God's love. Rolland Baker is the grandson of missionary H.A. Baker.