Substituted 6-(2-halogenphenyl)-triazolopyrimidines of formula I in which R1 denote alkyl, alkenyl, alkynyl, alkadienyl, haloalkyl, haloalkenyl, cycloalkyl, phenyl, naphthyl, or a 5- or 6-membered saturated, unsaturated, or aromatic heterocycle, containing one to four nitrogen atoms or one to three nitrogen atoms and one sulfur or oxygen atom, wherein R1 and R2 radicals may be substituted as defined in the description, R2 denote hydrogen, or a group mentioned for R1; or R1 and R2 together with the interjacent nitrogen atom represent a 5- or 6-membered heterocycle, containing one to four nitrogen atoms or one to three nitrogen atoms and one sulfur or oxygen atom, which ring may be substituted as defined in the description; Hal is halogen; L1, L3 independently denote hydrogen, halogen, or alkyl; L2 is hydrogen, halogen, haloalkyl, or NH2, NHRb, or N(Rb)2, wherein Rb is as defined in the description, wherein at least one from L1, L2, and L3 is not hydrogen; X is halogen, cyano, alkyl, alkoxy, haloalkoxy or alkenyloxy. processes for their preparation, compositions containing them and to their use for combating phytopathogenic fungi.