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An efficient dearomative (3 + 2) cycloaddition of <i>para</i>-quinamines and 2-nitrobenzofurans has been developed. This reaction proceeds smoothly under mild conditions and affords a series of benzofuro[3,2-<i>b</i>]indol-3-one derivatives in good to excellent yields (up to 98%) with perfect diastereoselectivities (all cases > 20:1 <i>dr</i>). The scale-up synthesis and versatile derivatizations demonstrate the potential synthetic application of the protocol. A plausible reaction mechanism is also proposed to account for the observed reaction process. This work represents the first instance of the <i>N</i>-triggered dearomative (3 + 2) cycloaddition of 2-nitrobenzofurans.