This paper discusses how organisational family culture is connected with organisational citizenship behaviour (OCB) with particular implication to business managers. The paper uses social exchange theory, person-organisation fit theory and relational psychological contract theory to explain how family-like cultural values characterised by cohesion, trust, mutual support, long-term orientation, and egalitarian norms influence the development of discretionary, non-mandatory employee behaviours that are not limited by the formal role requirements. Through a thorough analysis of both empirical and theoretical sources, it is evident that organisations that have developed family culture have much higher rates of OCB in its five dimensions: altruism, conscientiousness, sportsmanship, courtesy and civic virtue. The moderating variables such as perceived organisational support, quality of leader-member exchange and job satisfaction are critically discussed. The paper also outlines the implications of the study to business managers in practice with references to the design of an inclusive organisational culture, development of transformational leaders, and incorporation of family-oriented HR practices. Difficulties and possible constraints of family culture models are discussed as well. The paper concludes with a call to intensify managerial deliberateness in developing relational workplace climate, which stimulate sustainable OCB results.