Objective To investigate the relation of Human Leukocyte Antigen-DRs to Pre-eclampsia/eclampsia (PE/E) by reviewing the observational studies on PE/E. Methods We searched the MEDLINE/PubMed, EMBASE, The Cochrane Library and CBMdisc to July 2005, by combining free text with MeSH words. We assessed the quality of included studies, extracted and analyzed data. Results The odds ratio of fetal-maternal HLA-DR4 antigen frequency in case group versus control group was 2. 60 (95% CI 1.87 to 3.60) with statistical significance. The antigen frequencies of'other fetal-maternal HLA-DRs in case and control groups were not statistically significant. The antigen frequencies of the couple HLA DRs were not statistically significant between case and control groups. We found that neither the HLA-DR sharing between the couples nor between fetus and mothers in case and control groups were statistically significant. Conclusions The antigen frequencies of HLA-DRs between the couples may have no association with the development of PE/E. The fetal gene types may be related to the development of PE/E. The HLA-DR sharing in mothers and fetus and the couples may have no association with the development of PE/E.