Objective To analyze the prevalence of dental anxiety in jaw cyst patients treated by cyst plug after fenestration decompression and to discuss its possible correlative factors. Methods A questionnaire survey was conducted among a total of 198 adult outpatients treated by cyst plug after fenestration decompression in our department from Mar.2012 to Dec.2014. All patients completed the Modified Dental Anxiety Scale (MDAS) to evaluate the level of dental anxiety and the related factors. The data were analyzed by SPSS 22.0 software package. Results The prevalence rate of dental anxiety in the outpatients treated by cyst plug after fenestration decompression was 63.6% (126/198) in the present study; χ² test results showed significant differences in the prevalence rates of dental anxiety in regard to the factors of sex, age, marital status, Visual Analogue Scale (VAS) degree, and receiving initial treatment or not(P<0.05); Logistic regression analysis demonstrated that the risk factors of dental anxiety included sex, age, VAS degree, and initial treatment or not; and Spearman rank correlation analysis showed a weakly positive correlation between VAS degree and MDAS classification, and the correlation coefficient was statistically significant. Conclusion The prevalence rate of dental anxiety in jaw cyst patients treated by cyst plug after fenestration decompression is high. Dental anxiety is closely associated with sex, age, marital status, VAS degree, and being initial treatment or not; and a positive correlation is found between the cyst fenestration decompression pain degree and the MDAS anxiety level.