Penelitian ini bertujuan untuk mengetahui pengaruh naungan terhadap Determinasi Seks Embrio Penyu Lekang (Lepidochelys olivacea) di Lhok Pante Tibang, Kota Banda Aceh dan Pantai lepung Aceh Besar. Pelaksanaan penelitian dari bulan Februari sampai bulan Juni 2016 di Lhok Pante Tibang, Banda Aceh dan Pantai Leupung, Aceh Besar. Penelitian dilaksanakan secara eksperimental. Pada masing-masing lokasi pantai dibuat 5 sarang penyu bernaungan dan 5 sarang penyu tanpa naungan. Berdasarkan pengulangan di kedua pantai penelitian, maka terdapat 20 sarang penyu. Bedenga dibuat berukuran 3x3 m2 sebagian bangunan bedeng ditutup dengan jarring paranet yang memiliki interval cahaya matahari 70% dan sebagian bangunan bedeng lagi tidak diberi naungan sehingga terpapar matahari langsung. Inkubasi telur dilaksanakan selama 40 hari. Selanjutnya dari masing-masing sarang diambil 1 telur secara acak. Kemudian dilakukan koleksi embrio dan gonad embrio. Pembuatan sediaan hitologis gonad embrio dengan metode paraffin dan pewarnaan hematoksilin dan eosin. Parameter yang diamati adalah jenis kelamin embrio penyu, suhu sarang dan kelembaban sarang. Data dianalisis secara deskriptif. Hasil penelitian menunjukan bahwa rasio seks embrio betina terhadap embrio jantan pada Lhok Pante Tibang ternaungi adalah 5:0, Lhok Pante Tibang tidak ternaungi 3:0 sedangkan di Pantai Leupung ternaungi 2:1 dan Pantai Leupung tidak ternaungi 5:0. Dapat disimpulkan bahwa determinasi seks penyu lekang di Lhok Pante Tibang dan Pantai leupung di dominasi embrio penyu lekang berjenis kelamin betina. Satu ekor embrio jantan ditemukan pada sarang perlakuan naungan. Naungan menyebabkan penurunan suhu sarang dan peningkatan kelembaban sarang. Kata kunci : Penyu Lekang (Lepidochelys olivacea), embrio, naungan, rasio seks This study aims to determine the influence of shade on The Determination of Sex of the Olive Ridley Turtle Embryo (Lepidochelys olivacea) in Lhok Pante Tibang, Banda Aceh and Leupung Beach, Aceh Besar District. The research was conducted from February to June 2016 in Lhok Pante Tibang, Banda Aceh and Leupung Beach, Aceh Besar. The research was conducted experimentally. At each beach location, 5 turtle nests with shades and 5 turtle nests without shade were made. By repetition on both coasts of the study there were 20 turtle nests. Nests were made with the dimension of 3x3 m2. Some of nests were covered with paranets, which has 70% interval of sun light. The incubation of the eggs was held for 40 days. Next, 1 egg is taken randomly from each nest. Then the collection of embryos and gonadsof the embryo were carried out. The making of prepared histology of the gonads of the embryo is done by the method of paraffin and hematoxylin coloring ang eosin. The observed parameter is the gender of the embryo of sea turtles, nest temperature and humidity of the nest. Data were analyzed descriptively. The results showed that the sex ratio of female embryos to the male embryos in shaded nest in Lhok Pante Tibang is 5:0, nests without shade in Lhok Pante Tibang 3:0, while the ratio on the shaded nests in Leupung Beach 2:1, nests without shade in Leupung Beach 5:0. Thus, it can be concluded that the determination of embryo gender in Lhok pante Tibang and Leupung Beach is in the dominance of the female embryo. One male embryonic tail found in the nest shade. Shade treatment causes a decrease in temperature an increase in humidity nest. Keywords : Olive Ridley Turtle (Lepidochelys olivacea), embryo, shade, sex ratio