The invention relates to disinfectant compositions, containing (a) at least one quaternary ammonium salt of the general formula (Ib), and optionally, an amine of the general formula (Ia) wherein R1 represents C6-18 alkyl, R2 represents benzyl or C6-18 alkyl, R3 represents C1-18 alkyl or-[(CH2)2-O]n R6, where n=1-20, R4 and R5 independently of one another represent C1-4 alkyl, R6 represents hydrogen or optionally substituted phenyl and A is a monovalent anion or the equivalent of a multivalent anion of an inorganic or organic acid b) at least one alkanolamine of the general formula (II), wherein m and, if present, o and p independently of one another have the values 2 or 3 and x and y independently of one another have the values 0 or 1, or a corresponding salt. The mass ratio of the components in the formulas (I):(II) is between 20:1 and 1:20. The inventive compositions are characterised by an excellent bactericidal and in particular fungicidal action even in small application concentrations and are suitable for use as both disinfectants and preservative agents.
