In recent years, several previous works find out that there is a new fundamental plane for radiatively efficient AGNs and XRBs that its slope is steeper compared with that of radiatively inefficient AGNs and XRBs. In this work, we compile a sample of 57 radiatively efficient blazars to do the study of fundamental plane with radiatively efficient XRBs. We find radiatively efficient blazars also follow the fundamental plane. But the slope of the fundamental plane for radiatively efficient blazars of correcting anisotropism is different with previous work of radiatively efficient AGNs (1.2-1.3). Our results suggest that radiatively efficient blazars may have a new fundamental plane. It might be helpful for us to have a better understanding on theoretical models of radiatively efficient blazars.