5★STAR Grand Prix 2021 in Toyama was a professional wrestling event promoted by World Wonder Ring Stardom, held on September 23, 2021 at Wohlfahrt Toyama 2F Multipurpose Hall in Toyama, Japan. It served as the sixteenth and penultimate show for the company's annual round-robin singles tournament and included three remaining block matches from the field of 20 competitors.
