The invention discloses a culture medium for detection of lactic acid bacteria in a compound microecological preparation and a detection method, wherein the culture medium comprises the following components in parts by mass: 10-15 parts of tryptone, 5-10 parts of a beef extract powder, 5-8 parts of a yeast extract powder, 5-20 parts of glucose, 0.1-0.3 part of magnesium sulfate, 3-5 parts of sodium acetate, 10-20 parts of ammonium citrate, 0.05-0.1 part of manganese sulfate, 1-5 parts of Tween-80, 15-20 parts of an agar powder and 1000 parts of distilled water, wherein the pH is 5.0-5.8. The culture medium is simple in composition and convenient in preparation operation, and can eliminate interference of bacillus on detection of the total number of the lactic acid bacteria, so that only the lactic acid bacteria are grown on the counting culture medium, and the bacillus is not grown. The detection method mainly adopts the culture medium, the operation is simple, and a result is facilitated to be rapidly detected; and the lactic acid bacteria are grown on the surface of the culture medium, so as to be convenient for observation and analysis of the morphology of colonies.