This study aimed to survey the knowledge and clinical practice of dentists regarding antithrombotic drug management before dental procedures. All dentists who worked in Chiang Mai, Thailand between February 2014 and December 2014 were invited to answer the questionnaires via mail. The survey items consisted of 20 questions focusing on knowledge and clinical practice regarding antiplatelet therapy, warfarin therapy and guideline recommendations. From 186 invitation mails, 100 dentists (53.8 %) returned the questionnaires. Seventy-two percent of the participants recognized clopidogrel, while only 20 % knew ticagrelor. Over 90 % of the participants did not know the optimal duration of dual antiplatelet therapy after stenting. Approximately half of the participants discontinued aspirin before dental procedures in their patients, and 66.7 % of them required at least 7 days of discontinuation. Three quarters of the participants suspended P2Y12 inhibitors before their procedures, and 87.0 % of them required at least 5 days of discontinuation. Warfarin was discontinued in 71.6 %, 89.4 % and 93.5 % of the patients undergoing low-, moderate- and high-risk procedures, respectively. Approximately half of the participants were willing to perform low-risk dental procedures at the INR level of 2.1-4.0, while most of them preferred to perform moderate- and high-risk dental procedures at INR level of ≤2.0 (60.9 % and 72.5 %, respectively). All the participants were aware of the guideline recommendations, but there was a discrepancy between their practice and guideline recommendations to which they referred. The knowledge of antithrombotic therapy among dentists in Chiang Mai, Thailand was limited. A high percentage of dentists practiced differently from guideline recommendations. Some educational interventions should be done to improve the quality and safety of the medical care.