The electronic transport and field emission properties of a single-crystalline GdB44Si2 nanowire are studied. The atomic structure and elemental composition of the GdB44Si2 nanowire are characterized by transmission electron microscopy (TEM) using atomic imaging, energy-dispersive X-ray spectroscopy (EDS), and electron energy-loss spectroscopic (EELS) mapping. The electrical conductivity of the single GdB44Si2 nanowire is in the range of 46.8-60.1 S m-1. The in situ TEM field emission measurement reveals that it has a low work function of 2.4 eV. To realize a converged electron emission, a field evaporation pretreatment was used to clean the emission surface and to make a sharpened tip. The field emission probe measurement results show that the electron emission from the sharp GdB44Si2 nanowire is converged to a single field emission spot and it has a work function of 2.6 eV which is in agreement with the in situ TEM measurement. The stability of field emission current is also very good with a fluctuation of 1.4% in 20 min. With a low work function and stable emission current, the GdB44Si2 nanowire shows great promise for field emission applications.