A rhodacyanine derivative represented by the following General Formula (1), wherein, in General Formula (1), R1, R2, and R3 each independently represent an alkyl group which may be substituted； Y1 and Y2 each independently represent a hydrogen atom, a chlorine atom, or a fluorine atom provided that Y1 and Y2 do not represent hydrogen atoms at the same time； and X represents a counter anion. A pharmaceutical composition for treating leishmaniasis including the rhodacyanine derivative and a pharmaceutically acceptable carrier.
