Drug allergy and pseudoallergic reactions are main adverse drug reactions. Allergy is mainly induced by the immunogenicity of drug, drug metabolic products or drug additive. Pseudoallergic reactions may result from the irritation or activation of inflammatory material release. Pre-clinical evaluation of drug allergy and pseudoallergic reactions is included in immunotoxicity evaluation. Now there is no in vivo or in vitro method that could predict all kinds of allergy or pseudoallergic reactions due to the different mechanisms. In the past few years, FDA, SFDA OECD, ICH and WHO have published several guidelines on per-clinical immunotoxicity evaluation, however, no agreement has been reached on allergy and pseudoallergic reactions evaluation. This article reviews the requirements of allergy and pseudoallergic reactions in pre-clinical evaluation.