Aim Hikikomori, a social withdrawal syndrome, has been suggested to be rooted in family dynamics. Early parental bonding (PB) has been linked to attachment and adulthood relationship patterns, possibly impacting the emergence of hikikomori. These outcomes have been connected to early experiences of the parents themselves, suggesting their intergenerational ‘transmission’; we conducted two online cross‐sectional surveys to clarify the above hypothesis. Methods The first survey presents three groups: non‐hikikomori adults (C), non‐pathological hikikomori (Non‐PH), and pathological hikikomori (PH); the second involved parents of individuals categorized according to the abovementioned groups. PB and attachment were evaluated through the parental bonding instrument (PBI) and Relationship Structures‐Experiences in Close Relationships Scale (ECR‐RS). Results PH was associated with lower PBI ‘Care’, higher ‘Anxious’ and ‘Avoidant’ attachment, and the combination of ‘Affectionless Control’ PB and ‘Fearful‐Avoidant’ attachment. Non‐PH was linked to paternal ‘Neglect’, especially when combined with ‘Dismissing’ and ‘Fearful‐Avoidant’ attachment. A mediation role of attachment‐related ‘Avoidance’ between PB and hikikomori was confirmed. Parents of PH showed higher PBI ‘Protection’, ‘Avoidant’ and ‘Anxious’ attachment, and lower PBI ‘Care’: They were linked to paternal ‘Affectionless Control’ and ‘Fearful‐Avoidant’ attachment. Paternal ‘Neglect’ was overrepresented in parents of Non‐PH. Conclusions Our results suggest that PB and attachment are involved in the appearance of hikikomori. PH may be connected to family history of ‘Affectionless Control’ and ‘Fearful‐Avoidant’ attachment, whereas Non‐PH may be linked to ‘Neglectful’ parenting, which could promote attachment‐related ‘Avoidance’. Specific interventions aimed at enhancing parents' sensitivity and mentalization could reduce the risk and the severity of hikikomori.