McCready intentionally shot herself at her Arkansas home last week after years of battling addictions to drugs and alcohol. She was 37.
Her fiance had also recently died and her two young sons were taken away from her after her family said she was drinking and using drugs again.
People.com said a white hearse, escorted by two police cars, transported the singer's wooden casket to the service at Crossroads Baptist Church Tuesday.
Pallbearers included McCready's three brothers -- Timothy, Joshua and Skyler -- and some of her cousins.
"Mindy adored her two children. She wanted them to know that. Through much agony and pain, she went to heaven. She is no longer sick. She is healed. Thank you for all who are here. Please pray for those boys. No matter what, she will always be my little girl, sitting in her car seat, singing into a hairbrush. The world was her stage," People.com said McCready's mother, Gayle Inge, told the mourners gathered inside the church.
A memorial service is also being planned in Nashville by McCready's friends in the music industry.
McCready was known for her hits "I'm Still Here" and "Ten Thousand Angels." She was also a participant on TV's "Celebrity Rehab with Dr. Drew."