This study aimed to evaluate the growth of grey mangrove Avicennia marina seedlings under Libyan environmental conditions. The experiment involved importing grey mangrove seedlings from the United Arab Emirates in two phases. The imported seedlings were planted at the study site, specifically in the municipality of Tajoura. A soil mixture of sand and peat moss at a ratio of 3:1 was used, with well-drained containers provided. The seedlings received necessary nutrients through NPK fertilizer at a ratio of 20:20:20, and were gradually irrigated with saline water of increasing concentrations. These measures supported the emergence of new leaves and the stabilization of the seedlings during the initial months.The results showed that the duration and conditions of transportation had a significant impact on the success of the seedlings. In the first trial, the seedlings were transported for 12 days without sufficient irrigation, leading to the death of most of the seedlings. In the second trial, the transportation period was reduced to six days and greater care was provided, resulting in successful outcomes with a survival rate exceeding 80%. Morphological changes in the first batch of seedlings were monitored and documented for approximately five months, while those in the second batch were observed for two months. Monitoring results indicated continued seedling growth, including the emergence of new leaves and noticeable root branching, despite some differences between the two batches in morphological traits such as seedling height, stem diameter, leaf area, and root size. The second batch showed improved morphological traits, except for root size, which was greater in the first batch. Overall, the study demonstrated that the seedlings adapted well to Libyan environmental conditions................ Keywords:............ Mangrove seedlings, Coastal environment, Climate change, Sustainable development, Bioindicators