 In 1985, to support the return of the critically endangered Père David's deer to China, Lü Zhengcao helped found and chair the China Milu Foundation, now known as the China Biodiversity Conservation and Green Development Foundation.On 13 October 2009, Lü died in Beijing at the age of 105 by Western age reckoning, or at the age of 106 by the traditional age system.At the time of his death, he was the last survivor of the original generals of the People's Liberation Army.