ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh ekstrak daun Avicennia marina terhadap daya tetas telur ikan lele dumbo (Clarias gariepinus). Penelitian ini dilakukan di BBI (Balai Benih Ikan) Lukup Badak, Kec. Pegasing, Kab. Aceh Tengah, pada bulan Februari 2016. Penelitian ini menggunakan metode Rancangan Acak Lengkap (RAL) dengan enam taraf perlakuan dan empat ulangan. Sampel yang digunakan adalah telur ikan lele dumbo. Telur sehat terlebih dahulu diinfeksikan dengan telur yang terserang jamur, setiap wadah perlakuan terdapat 100 butir telur sehat dan 30 butir telur terinfeksi. Selanjutnya telur ini direndam dalam larutan uji ekstrak daun A. marina, dengan perlakuan konsentrasi 0, 10, 20, 30, 40, dan 50 ppm. Hasil uji ANOVA menunjukkan bahwa penambahan ekstrak daun A. marina berpengaruh nyata terhadap daya tetas telur ikan lele dumbo pada taraf kepercayaan 95%. Hasil uji lanjut Beda Nyata Jujur menunjukkan bahwa persentase daya tetas telur ikan lele dumbo berbeda antar perlakuan. Konsentrasi optimum ekstrak daun A. marina pada penelitian ini adalah 50 ppm dengan menghasilkan daya tetas telur sebesar 92%. Kata kunci : Saprolegnia sp., daya tetas telur, ekstrak daun Avicennia marina ABSTRACT This research aimed to determine the effect of leaf extract of Avicennia marina on hatching rate of African catfish’s eggs (Clarias gariepinus). This research was conducted in the fish hatchery, BBI (Balai Benih Ikan) Lukup Badak, Pegasing district in regency of Central Aceh, on February 2016. This research used a completely randomized design with six treatments level and four replications. The samples used were African catfish’s eggs. Previously, the health fertilized eggs were infected by the infected eggs by Saprolegnia sp., Each compartment contained of 100 health fertilized eggs and 30 infected eggs. Furthermore, the eggs were immersed in the test solution of Avicenna marina leaf extract, with the concentration treatment: 0; 10; 20; 30; 40; and 50 ppm. The ANOVA test results showed that the addition of Avicenna marina leaf extract significantly effect on the hatching rate of African catfish’s eggs at the significant level of 95%. The further test results of Honestly Significant Difference Test indicated that the percentage of hatching rate of African catfish’s eggs were different between leaf extract treatments. The optimum concentration of Avicennia marina in this research was 50 ppm the hatching rate value was 92%. Keywords : Saprolegnia sp., Hatching Rate, Avicennia marina leaf extract