Colletotrichum destructivum is the pathogen of anthracnose in Anthurium andraeanum. Based on internal transcribed space (ITS) sequences of Colletotrichum genus, a pair of specific primers (F1 and ITS4) to detect C.destructivum was synthesized. The primer sets amplified a single PCR band of 486 bp with DNA extracted from C.destructivum isolated from A.andraeanum,while other relative strains within different species had no corresponding band. The detection sensitivity was 10 pg of genomic DNA. When using ITS1/ITS4 as the first round primes and F1/ITS4 as the second round primes, the detection sensitivity increased 10 000-fold to 10 fg. The detection sensitivity for the soil pathogens was 200-conidia per gram soil. The PCR-based method developed here could stably and quickly detect the pathogen from water samples and diseased plants.