The purpose of this study was to examine the associations between daily habits, Streptococcus mutans, and caries using International Caries Detection and Assessment System Caries Index (ICDAS CI); and compare it to the DMF index.Altogether 122 children were examined and interviewed. Saliva and plaque samples were collected and analyzed by Dentocult SM ® Strip Mutans test. ICDAS CI was calculated by counting all ICDAS caries scores of all surfaces divided by total number of carious teeth.ICDAS CI was significantly (p<0.01) and strongly associated with DMFT/dmft (ρ=0.72), DMFS/dmfs (ρ=0.72), total number of carious teeth (DT/dt) (ρ=0.77), enamel caries surfaces (ρ=0.61) and dentine caries surfaces (ρ=0.75). Plaque S. mutans was significantly (p<0.05) correlated with ICDAS CI and DT/dt. Children who brushed once a day or more had significantly lower ICDAS CI (p<0.01). Children who consumed sweets or drank soft drinks more than once a day had significantly higher ICDAS CI (p<0.05). No significant association was found between ICDAS CI and frequency of flossing, use of mouthrinse, or gum chewing.ICDAS CI seems to have similar trends as DMF indices, but includes more information about the stage, severity, and progress of the caries lesions of the patient.