ABSTRAKEkosistem mangrove penting untuk dijaga karena berfungsi mengontrol ketersediaan bahan organik di perairan pantai untuk menunjang kehidupan organisme di perairan laut. Kegiatan penanaman mangrove merupakan salah satu upaya menjaga kestabilan ekosistem, dengan cara merehabilitasi ekosistem mangrove di suatu kawasan. Tingkat keberhasilan hidup dan tingkat pertumbuhan menjadi acuan dalam penilaian ini. Penelitian ini bertujuan untuk mengukur tingkat kelangsungan hidup bibit mangrove Rhizophora sp yang ditanam di wilayah pesisir Kuala Samboja. Penelitian dilaksanakan pada bulan Juni – Oktober 2022. Pengukuran bibit dilakukan pada awal dan akhir penelitian. Metode yang digunakan adalah survei dengan pendekatan kuantitatif. Data yang diperoleh terdiri dari bibit hidup dan mati, tinggi bibit, diameter bibit dan jumlah daun. Hasil penelitian menunjukkan bahwa tingkat kelangsungan hidup bibit mangrove sebesar 22%, yaitu dari 400 bibit pada awal pengukuran menjadi 89 bibit pada akhir pengukuran. Kondisi ini menunjukkan bahwa kegiatan tersebut memiliki tingkat keberhasilan hidup yang rendah. Pertumbuhan tinggi bibit 6,67%, diameter batang 21,4%, dan jumlah daun 4%. Kata Kunci: Mangrove, Laju Pertumbuhan, Kuala SambojaABSTRACTMangrove ecosystems are important to maintain because they function as controllers for the availability of organic matter in coastal waters to support the life of organisms in marine waters. Mangrove planting activities are one of the efforts to maintain ecosystem stability, by rehabilitating mangrove ecosystems in an area. life success rate and growth rate become a reference in this assessment. This study aims to measure the survival rate of mangrove seedlings of the Rhizophora sp species planted in the coastal area of Kuala Samboja. The research was conducted in June - October 2022. Measurements of seedlings were carried out at the beginning and end of the research. The method used is a survey with a quantitative approach. The data obtained was in the form of live and dead seedlings, height, diameter of seedlings, and number of leaves. The results showed that the survival rate of mangrove seedlings was 22%, from 400 seedlings at the beginning of the measurement to 89 seedlings at the end of the measurement. This condition shows that these activities have a low life success rate. The growth of seedling height was 6.67%, stem diameter was 21.4%, and number of leaves was 4%. Based on the results above, the height.Keywords: Mangrove, Survival Rate, Kuala Samboja