Han Wenhai began his professional football career with Dalian Shide and was one of the first goalkeepers in China to accept the guidance of British coaches to aid players achieve professionalism. This would greatly help him rise to prominence during the 1996 league season when he established himself as Dalian's first-choice goalkeeper and aided the team to win the league title. His performances would see him included in the Chinese squad that took part in the 1996 AFC Asian Cup where he played understudy to Ou Chuliang. This was then followed by several FIFA World Cup qualifying games, however he struggled to replace Ou as the team's goalkeeper and despite being called up to several squads he found another goalkeeper Jiang Jin pushing ahead of him for the goalkeeper position. At Dalian he remained the team's number one goalkeeper for the next several years and won three more league titles until he left at the end of the 2000 league season when he was replaced by Chen Dong.