Jetting fluidized transition velocity (u(jtv)) is investigated in a 300 mm x 50 mm 2D jetting fluidized bed with two nozzles for eight materials, including four binary mixtures. The experiments show that the peak in the curve major frequency versus jetting gas velocity corresponds to u(jtv). The u(jtv) increases with increasing nozzle distance, particle diameter, but decreases with increasing static bed height and nozzle diameter. A correlation is proposed for prediction of u(jtv).