Acts including Bethel Music, Reuben Morgan Hillsong Worship and Rend Collective will take to the stage at the festival, which is also hosting a second leg in Cheshire next weekend.
Tonight we finish of with 75mins of worship from @bethelmusic We wan't to see you all there! 8.45pm— BigChurchDayOut (@BigChurchDayOut) May 27, 2017
Also taking part, musician Tim Hughes from Tim Hughes & Worship Central told Premier: "If you think about 20,000 people gathering together for a weekend, what God can do in and through that I think is incredibly exciting.
"We're chuffed to bits to have a small part to play in being a part of that."
Organisers are promising "world-class music" on the Main Stage and several smaller venues, including the Tearfund Tea Tent and Christian Solidarity Worldwide Airstream Stage.
Tim Hughes went on to say: "We're excited about having an opportunity to lead people in worship.
"For us, it's not about trying to perform our new songs. It's about saying 'hey, this is the Church gathered together on this beautiful location in the open air - let's lift high the name of Jesus."
Casting Crowns, Switchfoot, Newsboys and Michelle Williams are joining this year's Big Church Day Out. The second leg is being staged at Capesthorne Hall near Macclesfield.
Other attractions include a ferris wheel, inflatables, bubble football, flower Hammocks and a Mission Aviation Fellowship flight simulator.
Tim Hughes added: "I believe when people worship, God shows up, God begins to engage with people, encourage them, speak to them, heal them, plant seeds and dreams in the future for them."
Click here to listen to Tim Hughes: