Best Buy Co. founder Richard Schulze is working with a Wall Street bank to explore taking the electronics retailer private, according to people familiar with his thinking, the latest twist in a tumultuous year at the company.

Mr. Schulze, the retailer's largest shareholder with a slightly more than 20% stake, abruptly resigned his post as chairman and a director of the Richfield, Minn., company earlier this month, saying he was pondering options for his shares.

People...