In 2007, he took part in the WTTC and reached Round 32 in singles again. In doubles, he reached the quarterfinals, setting a new record. At the Asian Championships he won silver with his team. In the doubles, he won bronze and reached Round 16 in singles. At the Asian Cup, he won bronze. In 2008, for the first time Mizutani won bronze with his team. At the Taiwan Open, he won bronze. At the Asian Cup, Mizutani played successfully and reached 4th place.