The Ca3-xBxCo4O9 system (x = 0.0, 0.05, 0.75 and 1.0) has been prepared using the solid-state reaction technique. Structural, microstructural, transport properties (temperature dependence of resistivity, thermoelectric power) of the samples fabricated were investigated in details. The structural/microstructural investigations showed that complex and multiphase crystallographic structure was formed with the B-substitution. A decrease in the grain size was observed in the B-substituted samples. The resistivity increased with the substitution due to decrease in the grain size and weak-link among the grains. It is found that that the thermoelectric power is insensitive to the B-substitution. The highest power factor value was obtained in the x = 0.0 sample, however, it decreased in the B-substituted samples.