Background Unsettled infant behaviours are a common source of concern for new parents and have been associated with perinatal common mental disorders amongst women in high‐income settings. There is little evidence about how unsettled infant behaviours are understood and managed in low and lower‐middle income countries. This study aimed to describe caregivers' understandings of, and responses to, unsettled infant behaviours in Vietnam and their family caregiving contexts. Methods Women who were mothers of infants aged 0–6 months were purposively recruited from two sites in Thua Thien Hue Province, Vietnam (one urban and one rural). An additional group of women who were grandmothers were recruited by snowball sampling. Data were collected in semi‐structured interviews about demographic information, infant feeding practices, descriptions of infant crying episodes, beliefs about why infants cry, settling strategies, infant sleeping arrangements and sources of advice on infant care. Translated interview transcripts were analysed thematically. Results Twenty‐four interviews were undertaken (21 with mothers and 3 with grandmothers). Five major themes emerged from the data after analysis: infant settling techniques, sources of information on unsettled infant behaviour, understandings of the causes of infant crying, the emotional responses of caregivers and the intergenerational household context. Infants were commonly cared for by people from multiple generations, particularly during the day. Infant settling was characterized by attending to infants immediately, breastfeeding and bed‐sharing with parents during the night. Most mothers received advice on caregiving from family members. Infant crying was attributed to hunger and loneliness, as well as traditional beliefs that the infant was being upset by ‘ghosts’ or becoming ‘hot’. Women described feeling anxious, frustrated and helpless in relation to unsettled behaviours amongst their infants. Conclusions Educational interventions on interpreting infant cues, infant sleep requirements and bed sharing may be appropriate in Vietnam if multiple generations are included and traditional beliefs about infant crying are addressed.