Cha married wife Lee Soo-jin in 1992. He and Lee are biological parents to daughter Cha Ye-ni (born 2003, christened as Rachel). In July 2014, a man claiming to be the birth Father of Cha and Lee's son Cha No-ah (born 1989, christened as Noah) filed (and quickly dropped) a ₩100 million defamation lawsuit against Cha, which led to the actor admitting that No-ah is Lee's son from her previous marriage, and that when he and Lee got married, Cha legally adopted No-ah who was then three years old. Cha had previously falsified his marriage date as 1989 to match No-ah's age, apologizing for the white lie since their son did not know his paternity.