The invention discloses a kind of appraisal bacterium, specially appraises the monk fungus (Salmonella), produces the uninuclear cell Liszt fungus (Listeria monocytogenes) the examination method. First (YAU_DSL1) separately uses the monk fungus and the backwoods coli the thermal crack solution to withdraw respective DNA template, produces the uninuclear cell Liszt fungus to use the enzyme solution to withdraw the DNA template, then carries on disposable PCR to expand increases the specific many genes, finally passes through the electricity to swim the appraisal. The invention through sample DNA, disposable at the same time to the monk fungus histidine transportation operon gene which possibly has, produces the uninuclear cell hemolysin gene to expand increases (YZU_DSL1) the material particle carries on with the certain existence backwoods coli expands increases, forms the massive genes duplication fragment, quite is convenient, can appraise whether for the monk fungus, produces the uninuclear cell Liszt fungus, and makes the judgement to the negative result reacting system accuracy. The invention more classical method bacterium separation, the appraisal and the blood serum school grades testing method fast, is accurate.