Purpose -This paper aims to provide a conceptual model for the purpose of examining potential influencing factors as well as particular effect of family SMEs' heterogeneity factors on EC adoption in Iranian family SMEs.Design/methodology/approach -The conceptual model originates from EC adoption study backgrounds, grounded in the major concepts of frequently EC adoption and their dependent-extended models. Literature review presents relevant items under their main first order factors, including family SMEs' heterogeneity factors, categorized by contexts.Findings -The model, in which EC adoption refers to the significance of 'Extent of Deployment' as innovation behavior, respecting to the theoretical basis of human behavior including essential pure theories (i.e. Learning; Anchoring-and-Adjustment) and major concepts of frequently EC adoption models (TAM; TPB; SCT; DOI), besides role of family SMEs' heterogeneity factors (i.e. The moderating effects of 'Family Strategic Orientation') provided a basis for assessing potential EC adoption antecedents (under which different facets of EC adoption would be considered) including 13 th first orders, categorized under four main individual, organizational, industrial, and national contexts.Practical implications -As a sustainable business market mean, EC adoption as an extra-exploitation of electronic commerce, making wider and more diversified external 'business-linked' and/or 'customer-linked' business relationships, particularly for family SMEs that suffer from 'marketing deficiency', time and effort is necessary so as to identify influencing factors and diagnose their effects on EC deployment in such Iranian SMEs, where EC adoption is questionably near to ground. The presented model is quite valuable for the analysis.Originality/value -This paper presents a conceptual model for analyzing EC adaption factors under related contexts. Independent influences of 12 first potential factors categorized in four contexts as well as the moderation effect of 'family strategic orientation' variable on EC adoption are studied in the model. The design differs from previous studies as they used dichotomous approaches for 'family strategic Orientation' determination.