Zhang Da'an (張大安) (died 684) was an official of the Chinese Tang dynasty, serving as a chancellor during the reign of Emperor Gaozong.
Zhang Gongjin died in 632 at the age of 38 and was eventually posthumously created the Duke of Tan and honored in one of the Portraits at Lingyan Pavilion, reserved for the greatest contributors to Emperor Taizong's reign.
By 677, he was serving on the staff of Li Xian, the crown prince of Emperor Gaozong (Emperor Taizong's son), when he was given the designation Tong Zhongshu Menxia Sanpin (同中書門下三品), making him a chancellor de facto.
Most of the staff members were pardoned, but Liu was exiled, and Zhang was also accused of flattering the former crown prince and demoted to the post of Pu Prefecture (普州, roughly modern Ziyang, Sichuan).
He died in 684, while serving as the military advisor to the prefect of Heng Prefecture (橫州, roughly modern Nanning, Guangxi).