Over 90 percent of votes cast at Carrefour's annual shareholders meeting approved the resolution relating to the appointment.

Diniz, who had been granted observer status on Carrefour's board in January, owns together with his family 8.05 percent of the capital of Carrefour and 7.09 percent of its voting rights.

The Diniz family is now Carrefour's third-largest shareholder, ahead of the 5.23 percent stake held by private equity firm Colony Capital, but still behind the 8.95 percent held by Groupe Arnault and the Moulin family's 11.51 percent.

In December 2014, Diniz also purchased a 10 percent stake in Carrefour's Brazilian unit, lifting it to 12 percent in June 2015. He has an option to raise that stake to 16 percent over five years.

(Reporting by Dominique Vidalon; Editing by Andrew Callus)