Department of Chemistry, Jadavpur University, Calcutta-32 Manuscript received 22 February 1974; accepted 4 April 1975 N-Benzoyl-phenylhydroxylamine has been used to determine 5.0 to 28.0 mg of manganese(II) gravimetrically. The complex is precipitated quantitatively within the \(p\)H range, 6.3 to 7.8. The interference due to Mg2+, As3+, Sb3+, MoO42-, WO42-, Cu2+, Co2+, Zn2+, Cd2+, Hg2+, Pd2+, UO22- or La3+ has been avoided by using tartrate, cyanide, ammonium carbonate or ammonium acetate as the masking agents. The reagent has also been utilised for the separation of Mn2+ from Ti4+, Fe3+, Sn2+, VO3-, Th4+ and Al3+ by adjustment of acidity. The precipitate is weighed as Mn(C13H10,O2N)2 after drying at 110°--120°. The accuracy is generally better than 0.3%.