The couple issued an apology to the public for the "negative social impact that this has created."
Reports had circulated online since May that Zhang, 62, had fathered seven children from two marriages and relationships with two other women. The People's Daily newspaper, published by the ruling Communist Party, reported that Zhang could face a fine of up to 160 million yuan ($26 million).
Chinese media reports said the lawsuit had little chance of succeeding because the two lawyers were not directly related to the case. Calls to the Wuxi Intermediary Court where it was filed rang unanswered.
Jia declined to rate his chances of success, saying only that, "We hope the court could handle the case in an innovative way and the public continue to monitor the development of the incident."
Zhang is one of China's most famous film directors, most recently of "The Flowers of War" starring Christian Bale. He also designed the opening and closing ceremonies for the 2008 Beijing Olympics.