A series of 5,8-dioxo-pyrimido[4,5-e][1,4]diazepine derivatives were designed and synthesized as new inhibitors against wild-type EGFR and a panel of mutants, including the clinical resistance related T790M mutants. One of the most potent compounds 2l inhibited all forms of EGFR evaluated with low nM IC50 values. It also strongly suppressed the proliferation of H1975 and HCC827 non-small cell lung cancer cells with IC50 values of 69 and 71 nM, respectively.