Recently a consistent well-defined 4-dimensional Einstein-Gauss-Bonnet theory of gravity was suggested in [K. Aoki, M. Gorji and S. Mukohyama, Phys. Lett. B 810, 135843 (2020)]. While quasinormal modes of bosonic fields for this theory have been recently studied, there is no such study for fermionic fields. Here we calculate quasinormal modes of the Dirac field for spherically symmetric asymptotically flat black hole in this consistent 4D Einstein-Gauss-Bonnet theory. The values of the quasinormal frequencies, calculated by the sixth order WKB method with Pade approximants and the time-domain integration, show that the real part of the quasinormal modes is considerably increased, while the damping rate is usually decreasing when the coupling constant is growing.