BACKGROUND: Neutrophils fixed on a slide are used in indirect immunofluorescence assay (IIF) for anti-neutrophil cytoplasmic antibody (ANCA). A simple method to prepare ANCA slides is described in this report. METHODS: This method uses an overlay method to separate WBC from EDTA whole blood and Octospottrade mark kits to cytocentrifuge WBC onto 8-well slides. This in-house ANCA IIF was compared with commercial ANCA IIF using 40 sera, and with enzyme linked immunosorbent assay for anti-myeloperoxidase (MPO) antibody (MPO ELISA) using 117 sera. RESULTS: In ANCA IIF parallel tests using 10 positive and 30 negative sera, in-house slides were in good qualitative agreement, 97.5% (39/40) with commercial kits (kappa=0.93). Fluorescence pattern and intensity of positive reaction was also highly concordant between two methods. In MPO ELISA positive cases, the positivity rate of in-house ANCA IIF was 97.8% (45/46), which accounts for its assay sensitivity for the presence of anti-MPO antibody. CONCLUSIONS: In-house ANCA slides was convenient and cost-efficient to be prepared. As these slides were found to have acceptable agreement and sensitivity as compared with commercial kits, in-house ANCA IIF is considered to be useful to screen ANCA in combination with MPO ELISA in routine clinical laboratory practice.