Dental radiography is an essential diagnostic tool in paediatric dentistry. To explore attitudes, knowledge, and related factors of paediatric dental radiography among parents who attended the radiology department of a premier public dental hospital. The study was conducted at the National Dental Hospital (Teaching) Sri Lanka among 124 parents whose children (<13-years) underwent dental radiographic examination. Data on sociodemographic characteristics, radiographic investigations, and parental knowledge and attitudes on paediatric dental radiography were collected using an interviewer-administered questionnaire. Data were entered and analyzed using the SPSS-21 statistical software package. The mean score (95% CI) of parental attitudes and knowledge on paediatric dental radiography were 17.55 (17.64-18.45) on a scale from 7 to 35 and 3.73 (3.34-4.13) on a scale from -7 to +7, respectively. Significant differences in parental knowledge were evident by child's age (p = 0.046), ethnicity (p = 0.035), and parental attitudes (p = 0.024). Binary logistic regression analysis revealed a significant independent association between parental attitudes with parental knowledge: OR (95% CI) = 2.413 (1.098-5.302) (p = 0.028). Parents demonstrated less favorable attitudes but sufficient knowledge on many aspects of paediatric dental radiography. Therefore, interventions are needed to improve parental attitudes on paediatric dental radiography especially by providing child-friendly services.