The lawsuit filed Monday in DeKalb County says Long, pastor of New Birth Missionary Baptist Church, and two business partners arranged to buy Hoops N' Fitness in Jonesboro in 2007.
The seller filed suit last year, claiming that none of the debt had been paid.
On Monday, the mortgage company, State Bank and Trust and the Federal Deposit Insurance Corp. filed suit against Long and his partners.
The new suit alleges the three parties owe $1.86 million on the defaulted loan, along with $32,000 in interest.
Long's spokesman, Art Franklin, says he's unfamiliar with the lawsuit and has no comment.