This study aimed to investigate the relationship between Early Childhood Oral Health Impact Scale (ECOHIS) and preschoolers’ fear and behavior during dental treatment. This cross-sectional study was conducted on 385 children aged 3 to 6 attending the pediatric dentistry department of Tabriz Faculty of Dentistry in their first dental appointment. Oral health related quality of life was measured with ECOHIS questionnaire and dental fear using Children’s Fear Survey Schedule (CFSS-DS) questionnaire. Frankle’s behavioral scale was also used for the evaluation of behavioral status. Data were analyzed by SPSS version13.0. ECOHIS score was correlated with CFSS-DS score (P<0.01) and Frakle’s behavioral scale. There was an association between ECOHIS and CFSS-DS score (B =0.198), and ECOHIS and behavioral status (B=-0.193). According to the results, the poorest oral health related quality of life was associated with high levels of dental anxiety and behavioral disorders. According to the results, there was an association between early childhood oral health related quality of life and the level of dental fear and behavioral status.