A team from the charity has been visiting areas recently liberated as it looks to support Christians caught up in the genocide.
Speaking to Premier from Iraq, ADF's Sophia Kuby told Premier: "What is striking to see is how intentional the destruction is.
"Every single sign of Christianity, of history, of tradition is destroyed.
"There is not one single sign of a cross in the churches. It has all been burned."
Tens of thousands fled areas of Iraq invaded by Islamic State after being told to convert, pay a fee or be killed.
Sophia Kuby says the subsequent actions of Islamic State show this is genocide.
"They didn't just want to expel the people," she said. "They wanted to erase their history, their churches. This is beyond words. You can see the amount of hatred."
Many areas of Iraq are being claimed back from Islamic State as coalition forces push the extremists back.
Listen to Sophia Kuby speaking to Premier's Marcus Jones: