Mothers of children with an intellectual disability often experience challenges that affect their mental health and the relationship with their children. The present study assesses the correlation between the mental health and relationship patterns of mothers of children with an intellectual disability. In this descriptive-correlational study, the mothers of 53 female and 92 male children with an intellectual disability were selected. The data were collected by: (a) a demographic questionnaire; (b) a general health questionnaire; and (c) the assessment scale of mother-child relationship. The results revealed that the acceptance relationship pattern had a significant negative correlation with somatisation (p = 0.006, r = -0.206), anxiety (p = 0.018, r = 0.174), and the general mental health (p = 0.009, r = 0.195). The rejection pattern had a significant positive relationship with depression (p = 0.026, r = 0.163). The present study showed that mothers who had experienced symptoms of anxiety or who had lower general mental health scores were less likely to use acceptance patterns in relationship with their child. Also, mothers who had symptoms of depression significantly rejected the relationship with their child. So, it is suggested that programs should be developed and implemented to maintain mothers' mental health.