Electronic properties of graphene nanoribbons (GNRs) doped with rhombus boron nitride segments are investigated by using first-principles method based on density functional theory. It is shown that band gaps of AGNRs increase owing to doping, and band gaps of AGNRs vary slightly as doped at different positions. In nonmagnetic states, ZGNRs are metal whether or not it is doped. In ferromagnetic states, ZGNRs change from metal to semiconductor due to doping. In antiferromagnetic states, ZGNRs are semiconductor whether or not it is doped, but band gaps are changed owing to doping. Structures of doped AGNRs and ZGNRs are stable, and ground state of doped ZGNRs is antiferromagnetic. It suggests that rhombus boron nitride segments doping controls effectively properties of GNRs, which is positive on future graphene nanoelectronic devices.