When air pushes a more viscous fluid in two parallel plates by a syringe pump, viscous fingering pattern have been observed. Water and aqueous glycerin solutions are used as Newtonian fluids, and aqueous glycerin solutions adding polyacrylamide (Separan AP30) are used as non-Newtonian fluids. It was found that it showed the bifurcation of viscous fingering to be different by a kind of solution. It was found that the solution concentration, gap and air pressure influenced a bifurcation pattern. Furthermore, viscosity and air pressure influenced tip speed of bifurcation in Newton fluid.