The present invention relates to active compound combinations, in particular within a fungicide composition, which comprise (A) fluoxapiprolin and (B) at least one biological control agent and/or (C) at least one compound selected from insecticides, acaricides and nematicides. Moreover, the invention relates to compositions comprising such compound combination and to the use thereof as biologically active combinations, especially for control of harmful microorganisms, in particular oomycetes, in crop protection.