Coffee beverage consumption is well-known to exert various health benefits; however, the effects of coffee aroma are rarely explored. This study aimed to investigate the calming effect of inhaling coffee aroma while the patients underwent dental procedures (probing and scaling). Salivary α-amylase (sAA) and cortisol (sCort) levels were measured as proxies of sympathetic nervous system and hypothalamic-pituitary-adrenal axis responses to stress respectively. Blood pressures and pulse rates were recorded. The results showed that undergoing dental procedures could increase sAA and sCort levels of the patients inhaling sham aroma while those inhaling coffee aroma had significantly decreased sAA and sCort levels (40% and 25% differences, respectively). The pulse rates of those inhaling coffee aroma were also lower. Subjective assessment using visual analog scale was in line with objective measures as well. The preference for coffee aroma or the frequency of coffee drinking had no effect on the sAA and sCort responses. This is the first study to provide evidence on the effect of coffee aroma on sAA and sCort levels in patients undergoing dental procedures.