He had attended a local youth center with the hopes of being taught Xiangqi (Chinese Chess); however, the trainer did not show up.

In the following month, he played on board 4 for the gold medal-winning Chinese team in the Under-16 Chess Olympiad in Kuala Lumpur.

Wang's first major tournament win was the Dubai Open in April 2005, when he was still untitled and finished clear first with a score of 7/9 points (rating performance of 2731), ahead of 53 grandmasters and 30 international masters.

[13] In August 2005, Wang won with 10/11 (two points clear ahead of the rest of the field) in the 2nd IGB Dato' Arthur Tan Malaysia Open in Kuala Lumpur (rating performance of 2843).

[17] In January 2008, at the 15th Asian Team Chess Championship in Visakhapatnam, Wang won an individual gold medal for his performance on board three (5/6).

[23] In November 2009, he competed in the FIDE World Cup: after defeating Joshua Friedel and Surya Shekhar Ganguly in the first two rounds, he was knocked out by Shakhriyar Mamedyarov.

[24] In the following month, Wang Hao won the Chinese Chess Championship scoring 7½/11 and edging out 2004 champion Bu Xiangzhi and Zhou Jianchao on tiebreak.

[25] In September 2010 he competed in the Grand Slam of Shanghai, a four players round-robin tournament, in which he played Levon Aronian, Alexei Shirov and Vladimir Kramnik.

[26] In a report on the 2010 Tal Memorial, the noted chess journalist Ilya Odessky writes that Levon Aronian "in his teasing style" named Wang Hao as the most talented player of the tournament.

[32] In June 2015, Wang Hao scored 6½/9 in the 10th Edmonton International Tournament, tying for the second place with Vassily Ivanchuk and Surya Shekhar Ganguly.

[33] On December 31, 2015 Wang won the 4th Al Ain Classic tournament scoring 8/9, 1½ points ahead of the nearest followers.

[36] The following month, he won the Asian Continental Championship in Chengdu, edging out Bu Xiangzhi on tiebreak score, after both players finished on 7/9 points (+5−0=4).

After the final game on April 27, 2021, he announced his retirement from professional chess, citing digestion-related health issues.