N-Heteropentacenes and their derivatives have been recently discoveredas a new family of organic semiconductors exhibiting high performancein organic field effect transistors (OFETs). Introducing nitrogenatoms to the pentacene moiety leads to a large number of structurallyrelated π-backbones with tunable electronic structures,stability, solubility, and molecular packing. This gives considerablefreedom when designing organic semiconductors and provides goodopportunities for studying structure-property relationships.In this account, efforts on developing N-heteropentacenes and N-heteropentacenequinonesas organic semiconductors are reviewed, with focus on the recentwork of our own group. 1 Overview 2 Brief Introduction to Organic Semiconductors and Organic FieldEffect Transistors 3 Dihydrodiazapentacenes and Diazapentacenes 4 A Dihydrotetraazapentacene and Its Methylated Derivatives 5 N-Heteropentacenequinones 6 Silylethynylated N-Heteropentacenes 7 Conclusion and Outlook