A method for rapidly screening a Phytophthora-nicotianae-antagonistic actinomycete strain is as follows: inoculating actinomycetes and Phytophthora nicotianae to a culture dish containing a PDA medium, and screening the Phytophthora-nicotianae-antagonistic actinomycete strain by measuring a bacteriostatic zone. Four rectangular strip band zones distributed around the center of the culture dish arearranged in the culture dish, the activated actinomycetes are spread in the four rectangular strip band zones, before inoculation of the Phytophthora nicotianae, the culture dish with the actinomycetes spread in is placed in an incubator for culturing for 2-4 days, the activated Phytophthora nicotianae is inoculated to the center of the culture dish, after the culture dish is placed in the incubator for culturing, the bacteriostatic zone is measured. Before inoculation of the Phytophthora nicotianae, the actinomycetes are inoculated in advance for culturing for a certain period of time, formation and release of antibiotics of actinomycetes strains are facilitated, the phenomenon of antagonism of the Phytophthora nicotianae can be fully demonstrated, effectiveness and pertinence of the screening of the antagonistic actinomycete are increased, the cost of repetitive testing is saved, and work efficiency is improved.