The ERBB2 nuclear transport in breast cancer cell lines after radiation and its possible role in radiation tolerance were observed. Confocal microscopy and Western blotting were applied to detect the nuclear ERBB2 expression after radiation in breast carcinomas cells. And the effects of Herceptin, AG825 and Cisplatin on the expression of nuclear ERBB2 were investigated. Survival fractions were also observed. After radiation, compared with control group, confocal microscopy and Western blot revealed that the expression of nuclear ERBB2 was increased in breast cancer cells time-dependently. Herceptin, and AG825 could significantly inhibit the radiation-induced nuclear ERBB2 expression, and decrease survival fractions. Cisplatin also induced the nuclear ERBB2 expression in breast cancer cells with high ERBB2 expression. It was concluded that radiation could induce ERBB2 nuclear transport, and nuclear ERBB2 may correlate with radiation resistance in breast cancer cells with high ERBB2 expression.