Parental burnout has been recognized as a significant family risk factor linked to problematic parental functioning and disruptions in overall family relational processes. However, to our knowledge, there is no validated instrument to study this construct in Greece. The present study therefore aimed to (a) validate the Greek version of the Parental Burnout Assessment (PBA) and to (b) examine whether conflictual parent–child interactions within the home learning environment (HLE) mediate the association between parental burnout and preschool children’s socio-emotional difficulties. Two independent samples of Greek parents with children aged 0–6 years were included (EFA sample: n = 128; CFA sample: n = 202). Exploratory and confirmatory factor analyses supported the original four-factor structure of the PBA (CFI = 0.982, SRMR = 0.047, RMSEA = 0.030) and demonstrated satisfactory psychometric properties. Correlational analyses indicated that parental burnout was positively associated with conflictual HLE interactions and children’s socio-emotional difficulties and negatively associated with prosocial behavior. Conflictual HLE interactions partially mediated the association between parental burnout and children’s socio-emotional difficulties; given the mediator’s nonsignificant correlation with prosocial behavior, mediation was not tested for that outcome, with indirect effects ranging from 0.028 to 0.095 (all p < 0.05). These findings extend the parental burnout literature by conceptualizing parental burnout as a family relational process associated with children’s socio-emotional adjustment through conflictual HLE interactions. The study discusses implications of these findings for family-centered prevention and intervention programs during early childhood.