Abstract: A newtype of concrete admixture is fabricated by mixing lithium-salt residue (LSR) and fly ash in a certain proportion. Experiments on this admixture show that: the addition amount of LSR affects the pozzolanic activity of the concrete admixture and the strengths of concrete aged 7 d, 28 d and 60 d respectively. Moreover, some modern test technologies, such as scanning electron microscopy and X-ray diffraction, are used to studythe pozzolanic activityof the concrete admixture and the morphology features of hydrated cement in their initial and later stages. The optimum content of LSR in the compound admixture is obtained.