Since his practicing year in 2003, Lawyer Zhang Hai has focused on civil litigation and criminal defense, has undertaken a large number of successful cases with great social impact, including many cases of innocence and non-prosecution, and has been awarded the title of Advanced Individual at the Urban and Urban Levels of the Judicial System seven times.

In 2016, he won the second prize of the Shandong Province Lawyers Association.

In 2007, he was invited to give a keynote speech at the Shandong Lawyers Forum. The title of the speech was "China Lawyers Should Lead Public Interest Litigation." Won the first prize in the 2007 Shandong Lawyers Forum Paper and the third prize in the 2009 criminal paper "On the Object of Credit Card Fraud".

In 2021, the criminal paper "On the Imprisonment of Misdemeanor Acts of Internet Violence and the Single Penalty" won the third prize.

In 2016,"The Fair Dream of Lawyers from a Great Power-Classic Cases of Famous Contemporary Lawyers in China" published by People's Daily Press,"Income from the Collection of Three Major Litigation Business Excellent Cases" by Shandong University Press. Many cases were reported on the New Statement column of Qingdao TV.