Analytical expression of electrical potential caused by a point current source in horizontally layered model was applied to analyze the distributions of sensitivity coefficients with the spacing and depth of electrodes when Schlumberger arrays were used in deep-well apparent resistivity measurement. The results showed that for a fixed Schlumberger array sensitivity coefficients displayed complex variations with the increase of electrode depth. Disturbances from surface might be amplified when deep-well measurement was made within some depth ranges for some electrical structures. For the fixed electrode depth，measurement using narrow electrode spacing mainly reflected resistivity information of the stratum where the arrays were. Information from deep stratum increased with the expansion of electrode spacing. Sensitivity coefficients of shallow layers generally increased at first and decreased afterward. When electrode spacing was large enough，difference of sensitivity coefficients between deep-well and surface measurement decreased. As an example，sensitivity coefficients of deep-well measurement at Tianshui seismic station were also analyzed. The calculated results could be used as a reference for choosing buried depth and spacing of the electrodes when deep-well configuration was used in different electric structures.