Chronic granulomatous disease (CGD), a rare inherited primary immunodeficiency disorder, is caused by mutation in any one of the genes encoding components of nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase enzyme. NCF2 gene (encoding P67-phox component) is one of them and its mutation is less common to cause CGD (around 5-6%). Here, we assessed mutation analysis of NCF2 in 4 CGD patients with p67-phox defect in Iran. These patients showed classical CGD symptoms. NCF2 sequence analyses revealed two different homozygous mutations including a nonsense mutation in exon 4, c.304C>T (Arg 102X) in one case and a CA deletion in exon 13 (Leu346fsX380) in one brother and sister; the latter is a new mutation which has not been reported in previous studies. In another patient in whom the attempts to amplify exon 2 individually from genomic DNA were unsuccessful, PCR amplification of exon 2 revealed no band of this exon on agarose gel. A PCR amplification mix of exon 2 and exon 7, with an internal control, confirmed the lack of exon 2 in this patient. Although a gross deletion in other exons of NCF2 has been previously reported, a large deletion encompassing exon 2 has been not reported yet. This abstract was also presented in ESID 2012, Florence, Italy.