The study aimed to examine the impact of corporate social responsibility (CSR) practices on organizational sustainability and to identify the mediating role of organizational citizenship behaviour (OCB) among employees at Palestine Technical College – Deir al-Balah. A descriptive-analytical approach was adopted, and data were collected through an electronic questionnaire due to the exceptional circumstances of war, which prevented direct fieldwork and regular presence at the college, leading to reliance on electronic work modalities. The study population consisted of 168 employees, with 81 valid responses analysed. The instrument comprised 50 items measuring CSR practices across six dimensions, OCB across five dimensions, and organizational sustainability across four dimensions. The results indicated relatively high levels of the main variables, with mean scores of 3.69 for CSR, 3.72 for OCB, and 3.66 for organizational sustainability. Strong positive correlations were found between CSR and OCB (r = 0.85), OCB and sustainability (r = 0.86), and CSR and sustainability (r = 0.89). The findings confirmed statistically significant positive effects of CSR on OCB, and of OCB on sustainability, in addition to a direct effect of CSR on sustainability. Mediation analysis revealed a partial mediating role of OCB in the CSR–sustainability relationship, indicating that part of CSR’s impact on sustainability is achieved through enhancing employees’ positive and voluntary behaviours. The study recommends adopting CSR within an integrated strategic framework, strengthening OCB and employee participation, linking social practices to sustainability goals, and developing electronic work systems, continuity planning, and crisis management to enhance the college’s resilience, adaptability, and sustainability.............. Keywords:............. Corporate Social Responsibility; Organizational Citizenship Behaviour; Organizational Sustainability; Technical Education Institutions; Palestine Technical College – Deir al-Balah.