The invention discloses a placental tissue preservation liquid and a preparation method thereof. The placental tissue preservation liquid includes glucose injection, a serum replacement, gentamicin, amphotericin, trehalose and heparin lithium. The preparation method of the placental tissue preservation liquid includes adding the serum replacement, gentamicin, amphotericin B, magnesium ascorbyl phosphate hydrate, trehalose and heparin lithium into the glucose injection, wherein final concentrations of the ingredients are 0.5-2%, 800 U / mL, 15-30 ug / mL, 0.25-0.5 mg / mL, 0.6-3 mg / mL, and 20-40 U / mL. The placental tissue preservation liquid has clear composition and balanced nutrition, has no evident toxic and side effects on cells, can well maintain activity of in-vitro placental cells, and iseffective in preventing contamination of exogenous microorganisms introduced in the acquisition and transport steps.