Existential well-being (EWB) and spirituality issues are important factors in determining quality of life (QoL) in amyotrophic lateral sclerosis (ALS) patients. No conclusive data among the relation between patient's EWB, their spirituality and caregivers' QoL are available. In the mainframe of a longitudinal study, we performed a cross-sectional analysis aimed to investigate EWB and spirituality issues in sporadic ALS (SALS) patients and the relations with caregivers' psychological features. Thirty-seven SALS patients, together with their caregivers, consecutively recruited at NEuroMuscular Omnicentre, in Milan, were included in this study. EWB and spirituality questions were administrated to patients and caregivers. Caregivers also completed questionnaires about quality of life (MQoL-SI), care burden (ZBI), depression (BDI) and anxiety (STAI). Both EWBs and questions about spirituality of SALS patients showed a positive correlation with MQoL-SI and EWBs in their caregivers. Conversely, SALS patients' EWB and spirituality were negatively correlated with caregivers' STAI, BDI and ZBI scores. In conclusion, existential well-being, as well as spirituality issues, perceived by SALS patients seems to be directly related with quality of life, severity of mood disturbance and burden experienced by their caregivers.