Abstract: Age a nd growth o f crucian car p ( Car assius aur atus) in Dali Lake, a sa linealkaline la ke situated in the Inter-Mongo lia platea u were studied. Bo th the third ray o f anal f in ( Spino us so f t ra y) and scale we re used as the materia l fo r a ge determinat io n. The result show ed that the scale w as a better mater ial fo r age determina tio n at the age below 5, whi le the third ray o f anal f in w as a superior o ne at the age 5 and abo ve. The V on Be rta lanf fy grow th equat ions as fo llow s: Lt= 30. 1 1- e- 0. 179 7( t + 0. 558 9) ; .. Wt= 832. 3 1- e- 0. 179 7( t 0. 558 9) 3 which wer e established based o n the age, length at age and w eight a t age, which indica ted a higher growth speed than that in 1970 ' s. Considering the decl ining o f the yields in r ecent years, w e suggest her e tw o management measures o f impr oving spaw ning co ndit io n and co ntr ol the capture size f or the conserv atio n o f resour ce.