Since 1989, the National Institute for Occupational Safety and Health (NIOSH) considers the Laboratory Animal Allergy - LAA a risk for workers and in 1998 the LAA has been recognized as occupational risk in the USA. Rat and mouse are the most source of allergens, not so much for the higher power of allergy respect to the other animals, but because represent the more utilized species in the research. Most of the allergens are members of the lipocalin superfamily, small extracellular proteins represented by at least 50 proteins that mainly bind or carry small hydrophobic molecules. The recent and innovative molecular techniques, as the microarray, have allow the characterization of numerous allergens. The protein microarray gives the possibility to study of IgE profile for each individual, simultaneos analysis of a wide number of parameters concerning the allergy, giving new diagnostic and therapeutic opportunities for the allergies. In the study of occupational allergy--as LAA--the protein microarray could improve: the identification and characterization of new allergens; the individuation of susceptible workers; the study of immunological responses in exposed workers; the strategies of prevention and protection; the environmental and housing conditions. The participation, formation and information of the workers could improve the behavioural and occupational practices, the use of personal and collective protective devices in order to reduce the exposure to LAA in occupational context.