InP quantum dots (QDs) are nontoxic emitters, which are considered an alternative to CdSe-based QDs. However, the limited choice and high cost of P precursors have a negative impact on their practical applicability. In this work, we report the large-scale synthesis of highly luminescent InP@ZnS QDs from an elemental P precursor (P4). The size of the InP QDs were controlled by varying the reaction parameters and their quantum yield could be increased up to 60%. Furthermore, possible reaction pathways have been investigated with nuclear magnetic resonance spectroscopy and it was demonstrated that the direct reaction of P4 precursor with In precursor produces InP structures without the formation of intermediate species. The largescale production of InP@ZnS QDs was demonstrated by yielding more than 6 g of QDs per one-batch reaction. We believe that the newly developed approach bears the potential to be widely used for manufacturing inexpensive high-quality QD emitters.