<p><b>Background:</b> The adult attachment dimension of attachment anxiety has been demonstrated to be associated with a variety of anxiety symptomology, including worry, intolerance of uncertainty (IU) and reassurance seeking. A variety of research has indicated that IU is associated with level of worry and reassurance seeking. The relationships between attachment anxiety, worry, IU and threat-related reassurance seeking have not been subject to investigation. The present article reports the results of an investigation of these variables within a community sample.</p><p><b>Methods:</b> Three-hundred and twenty-eight participants were recruited to complete an online survey in which participants completed the Intolerance of Uncertainty Scale, the Experiences in Close Relationships Scale-Revised, the Penn State Worry Questionnaire and the Threat-related Reassurance Seeking Scale.</p><p><b>Results:</b>Attachment anxiety, IU and worry were correlated with threat-related reassurance seeking. Consistent with previous research, IU was found to mediate the relationship between attachment anxiety and worry. IU and worry were found to be serial-multiple mediators in the relationship between attachment anxiety and threat-related reassurance seeking.</p><p><b>Conclusions:</b>The results of the study suggest IU is likely to play a key role in the relationship between attachment anxiety and worry, as well as the relationship between attachment anxiety and threat-related reassurance seeking.</p>