Siân Rees, who is originally from Aberystwyth, is also joining the UK-wide leadership team of the EA - the largest and oldest group seeking to draw together the country's evangelicals.
She said: "I am passionate about equipping, releasing and championing others to become all that God has created them to be.
"I'm excited to be taking up this role and believe that the Evangelical Alliance is uniquely placed at this time to envision, unite and mobilise churches and Christians across Wales and the UK in order to extend the kingdom of God."
Siân Rees has most recently been leading the performing arts department of a North Wales secondary school. Previously, she undertook a sabbatical studying at Hillsong International Leadership College in Sydney.
Steve Clifford, general director of the Evangelical Alliance, said: "We are delighted to welcome Siân Rees as our new director of the Evangelical Alliance in Wales and member of the UK leadership team.
"Siân is a first language Welsh speaker who lives with a passion to see the church in Wales rise to the challenge of making Jesus known to the diverse communities which make up the nation.
"Siân brings wide experience both inside and outside the Christian community, and we are looking forward to benefiting from all she will bring to the Evangelical Alliance, both in Wales and across the UK."
Siân read music at Bangor University. She is currently part of the leadership team at the Welsh-speaking Caersalem Church in Caernarfon.
Consisting of hundreds of organisations and thousands of churches, the EA is also the founding member of the World Evangelical Alliance - an umbrella body for evangelical alliances across the globe.
Last summer, the general secretary of the World Evangelical Alliances told Premier the term "evangelical" has become more closely associated in the US with politics than Christianity - and it must be "reclaimed".
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