This study demonstrated the foaming agent spray concept to achieve separate control of the application of deinking chemicals, i.e., foaming agent and collector, in flotation deinking of waste paper. Batch flotation experiments were conducted using two commercial cells, i.e., Voith Sulzer flotation cells with 18-L capacity (E-18) and 250-L capacity (E-250), to deink old newsprint paper (ONP) and a mixture of ONP with old magazine paper (OMG), respectively. It was found from this study that the deinking efficiency could be significantly improved and fiber loss could be reduced if the foam in the flotation cell was suppressed by adding a defoamer and then regenerated at the top layer of the flotation pulp suspension using a foaming agent spray technique from the top of the flotation cell. Compared to a conventional flotation process, the new process reduced the fiber loss during the flotation by about 50% with the same brightness gain (around 9) for deinking ONP and a mixture of ONP and OMG. Successful demonstration of scale-up of the frothing agent spray concept in the laboratory was observed in deinking a mixture of ONP and OMG using both the E-18 and E-250 cells.