Objective To investigate the clinical features and genetic basis of cryopyrin-associated periodic syndrome (CAPS). Methods The clinical manifestations, laboratory tests, and genetic tests of one case of CAPS were retrospectively analyzed. The related literatures were reviewed. Results A 7 year and eight month old male patient had recurrent fever for 7 years and his whole body was covered with patchy red rash which was itchy and faded with pressure. The limbs and joints were normal. The levels of high-sensitivity C-reactive protein, erythrocyte sedimentation rate, rheumatoid factors were increased. The patient had fundus arteriosclerosis, double conjunctival lesions and nerve deafness on both sides. There was no mutation found in NLRP3 gene coding region, but a heterozygous mutation (-2667G>T) had been found in 5 ' untranslated region. Compared with normal control, the mRNA level of NLRP3 increased 4.2 times and the expressions of IL-1βand IL-18 gene increased 2.2 (P=0.002) and 1.2 times (P>0.05). Conclusions The clinical features of CAPS can be recurrent fever, rash, and joint involved. The oph-thalmologic abnormalities and varying degrees of deafness may occur during the progression. The test of NLRP3 gene may help diagnosis.