Ba0.6Sr0.4TiO3-MgO-based ceramic slurries with B2O3 and Li2CO3 as sintering aid were prepared with different solvent systems for tape casting application. The effects of azeotropic mixtures of toluene-ethanol, methyl ethyl ketone (MEK)-ethanol and zeotrpic mixture of xylene-ethanol with a mass ratio of 50:50 on Ba0.6Sr0.4TiO3-MgO-based nonaqueous suspensions with B2O3 and Li2CO3 as sintering aid were investigated by sedimentation test, rheological measurement, density measurement, and SEM analysis. Without organic additives added, suspensions prepared with the MEK-ethanol mixture present higher flowability with lower viscosity, but less stability because of the smaller viscosity and density of MEK. On the other hand, with organic additives added, the gel structure is formed in slurries prepared with the toluene-ethanol mixture and xylene-ethanol mixture, caused by the reaction of the functional hydroxyl group of PVB and dissociated borate in the slurries. While slurries prepared with the MEK-ethanol mixture were more stable, exhibiting nearly Newtonian flow behavior and significantly lower viscosity.