Charge control agent and toner using same

The present invention provides a charge control agent containing one or more thiazolidinedione derivative, represented by general formula (1) below, as an active constituent. [In the formula: R1 represents a hydrogen atom etc. R2 represents a linear or branched alkyl group etc. with 1 to 8 carbon atoms, which may have hydrogen atoms and substituents; R3 to R7 may be the same as each other or different to each other, and comprise linear or branched alkyl groups with 1 to 8 carbon atoms, which may have hydrogen atoms, chlorine atoms and substituents, linear or branched alkenyl groups with 2 to 6 atoms, which may have substituents, and linear or branched alkyloxy groups with 1 to 8 atoms, which may have substituents, and said R3 to R7 may bond to each other to form rings. V, W, X, Y and Z represent carbon atoms or nitrogen atoms, where 0 to 3 of any of V, W, X, Y and Z are nitrogen atoms. The nitrogen atoms in this case do not have the substituents of R3 to R7.]