Despite high prevalence of anxiety, current interventions for family carers of people with dementia are considered to be not as effective for anxiety as they are for depression. Understanding the mechanism by which a common stressor (i.e. carer subjective burden) and underlying psychological processes influence anxiety among this population is critical to inform these interventions. Roles of two psychological processes were explored: experiential avoidance in caregiving (attempt to control distressing thoughts/feelings related to caregiving) and cognitive fusion (tendency for one’s behaviour to be overly regulated by thoughts). With a sample of seventy-seven family carers, this study examined the indirect effect of carer subjective burden (ZBI-12) on anxiety (GAD-7) through experiential avoidance in caregiving (EACQ) and cognitive fusion (CFQ) using path analysis approach. The whole sample model showed a good fit to the data and accounted for 54 % of the variance in anxiety. The indirect effect of carer subjective burden on anxiety through its effect on cognitive fusion (β = 0.17), and its combined effect on experiential avoidance in caregiving and cognitive fusion (β = 0.01) were significant. Given the higher explanatory value of cognitive fusion alone, facilitating cognitive defusion through psychological interventions may be critical for preventing clinically significant levels of anxiety, particularly among those carers experiencing high levels of carer subjective burden. Results also demonstrated that carers with higher experiential avoidance in caregiving may be prone to cognitive fusion, which in turn could lead to greater anxiety. Therefore, early interventions targeting experiential avoidance may be beneficial for preventing increased cognitive fusion and anxiety.