In order to investigate the characteristics of generation mechanisms of large-scale Birkeland currents from the standpoint of relative importance of a voltage source and a current source, we have determined quantitatively the relationships between large-scale Birkeland current intensities and ionospheric conductivities under geomagnetic quiet conditions. The large-scale Birkeland currents are the well-defined region 1 and region 2 systems that were determined from transverse magnetic disturbances acquired with the Magsat satellite over the entire polar regions except for the midnight sector. The ionospheric conductivities were determined by solar EUV ionization. The principal results include the following: (1) The region 1 and region 2 systems exhibit different dependence on ionospheric conductivities. The region 1 current intensities are proportional linearly to the conductivities at all MLTs. The region 2 currents also show a dependence on ionospheric conductivities, but they have in general poorer correlations at all MLTs than the region 1 currents have. (2) The correlations with conductivities are improved by using the region 1 current density and the region 2 current latitudinal width. (3) The degree of the coupling between the region 1 system and the region 2 system seems to have no correlation with conductivities. (4) The above-mentioned characteristics are common both in the northern and southern polar regions. These findings suggest that the large-scale region 1 system is primarily driven by voltage generators in the magnetosphere. On the other hand, the region 2 system seems to be driven by a combination of voltage and current generators. ¿American Geophysical Union 1987