Considering　the　effect　of　the　interface　spin-flip　scattering,　the　spin-injection　across　ferro-magnet/nonmagnetic-semiconductor/ferro　magnet　heterostuctures　with　finite　size　was　explored　theoretically.　Due　to　the　fact　that　interfacial　spin-flip　scattering　leads　to　spin-memory　losses　at　the　interfaces,　the　spin-up　component　of　spin-polarized　current　could　not　be　continuous　across　the　interface.　It　is　found　that　when　the　spin　injection　efficiency　varies　from　zero　to　unity,　the　tunneling　magnetoresistance　of　the　ferromagnet/nonmagnetic-semiconductor/ferromagnet　junction　presents　two　orders　of　changes　in　magnitude,　which　reflects　the　fact　that　the　spin-flip　scattering　at　the　interface　directly　affects　the　tunneling　magnetoresistance　of　ferrom　agnet/nonmagnetic-semiconductor/ferromagnet.