Melting of phosphorus in the 2.0-7.7 GPa pressure range has been studied by in situ electrical resistivity measurements (the results are shown in Fig. by red semi-filled stars). The experimental points at 2.0 and 2.4 GPa apparently reflect the melting of orthorhombic allotrope, while all others correspond to the melting of rhombohedral phosphorus. The melting curve of rhombohedral allotrope exhibits positive slope of 58 ( 2) K/GPa that points to a lower density of the melt as compared to the solid phase.