OBJECTIVE The objective of the present study was to evaluate whether sensitivity to bitter taste and perception of sweet taste have an influence on dental caries in urban and rural areas. METHODS The caries experience in 181 children, aged 12 years, from rural and urban areas of southern Brazil, was assessed according to World Health Organization guidelines. Sensitivity to the bitterness of phenylthiocarbamide was determined using the Harris–Kalmus procedure, and the sweet taste thresholds of sucrose were measured by Nilsson and Holm's method. RESULTS The caries index (DMFT > 0) was 3.73 (SD = 2.26) in the rural area and 3.51 (SD = 2.14) in the urban area. The sensitivity to bitter taste and sweet taste perception showed significant association with the gender of schoolchildren (P = 0.04). Girls were predominant in the high sweet perception taster group (62.3%) and the bitter taster group (59.4%). No significant difference in sweet perception status could be observed between the groups of low and high caries severity. The genetic ability to taste bitterness significantly influenced the levels of caries only in children from the urban area (P = 0.005). Bitter non-tasters presented higher severity of caries. A positive correlation was observed between sensitivity to bitter taste and sweet taste perception among children in the rural (r = 0.42, P = 0.002) and urban areas (r = 0.36, P = 0.001). CONCLUSIONS These findings suggest that the bitter non-tasters are more susceptible to dental caries than the tasters in the urban area.