Malate dehydrogenase(MDH) is an important enzyme in glycometabolism. MDH of Apis mellifera showed three enzyme active zones, MDHI,MDHIIand MDHIII. MDHIand MDHIII maintained relative stability in different castes and developmental phases,but MDHIIwas polymorphic,and controlled by three alleles,a,b and c.MDH of Apis cerana was coded by S and F alleles,but some authors reported it is monomorphic.MDH was applied to the studies of A. mellifera, which included several aspects as follows: the number of queen matings,labor division in honeybee societies, the analysis of genetic constitution in honeybee populations and so on. The combination of both MDH and molecular biology will certainly promote honeybee studies.