Diane Marie Hendricks (born 1947) is an American businesswoman, film producer, and philanthropist from Wisconsin. She is the widow of businessman Ken Hendricks.
Hendricks was born and raised in Wisconsin, the daughter of dairy farmers. She graduated from Osseo-Fairchild High School in 1965, and had been divorced from her first husband for ten years when she met Ken Hendricks.
In 1975, she was selling custom-built homes and Ken was a roofing contractor. They married and became business partners. In 1982, they used their lines of credit to secure a loan that enabled them to establish ABC Supply. ABC Supply is privately held, and sells roofing, windows, gutters, and siding for residential and commercial buildings.
Diane Hendricks owns the Hendricks Holding Company, and is the owner and chairperson of ABC Supply. In March 2012, Forbes estimated her net worth at US$2.8 billion; Forbes estimated it at $4.3 billion as of January 2017.
She is a donor to WisconsinEye, and co-chair of Rock County 5.0, a five-year public/private initiative to advance Rock County’s economic development vision. She has served on the boards of the Stateline Boys & Girls Club, Beloit Memorial Hospital, the Beloit Foundation, Forward Janesville, Kandu Industries, Blackhawk Bank, and the Hendricks Family Foundation. Hendricks serves on the Board of Trustees of Beloit College.