ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh fotoperiod terhadap pertumbuhan dan kelangsungan hidup larva ikan peres (Osteochilus kappeni). Penelitian bertempat di Unit Pelaksanaan Teknis Balai Benih Ikan Lukup Badak Kecamatan Pegasing Kabupaten Aceh Tengah pada bulan Agustus sampai September 2016. Metode penelitian yang digunakan adalah metode eksperimental dengan Rancangan Acak Lengkap (RAL), terdiri dari lima perlakuan dan tiga kali ulangan. Perlakuan yang diberikan adalah A (tanpa perlakuan), B (15 T : 9 G), C (18 T : 6 G), D (21 T : 3 G), dan E (24 T : 0 G) dengan menggunakan lampu Light Emitting Diode (LED). Hasil uji ANOVA menunjukkan bahwa variasi periode penyinaran pada larva ikan peres berpengaruh nyata terhadap pertumbuhan panjang mutlak, berat mutlak, laju pertumbuhan spesifik, koefisien keragaman panjang, dan kelangsungan hidup. Hasil uji Duncan menunjukkan bahwa perlakuan terbaik ditemukan pada perlakuan D (21 T : 3 G) dengan nilai rata-rata pertumbuhan panjang 1,4 cm, pertumbuhan berat 0,07 gram, laju pertumbuhan spesifik 0,30%/hari, koefisien keragaman panjang 1,83%, dan kelangsungan hidup 89,33%. Kata kunci : ikan peres (Osteochilus kappeni), periode penyinaran, pertumbuhan   ABSTRACT This research aimed to determine the effect of photoperiod on the growth and survival rate of peres fish larvae (Osteochilus kappeni). The research was conducted at technical implementation unit of fish breeding center Lukup Badak, Pegasing district, Aceh Tengah on August until September 2016. The method used was Completely Randomized Design (CRD) consisted of five treatments and three replications. The treatments were A (control), B (15 L : 9 D), C (18 L : 6 D), D (21 L : 3 D), and E (24 L : 0 D) using Light Emitting Diode (LED) lamp. The result of ANOVA test showed that the variation of photoperiod gave significant effect on the length growth,weight growth, specific growth rate, long diversity coefficient, and survival rate of peres fish larvae. The Duncan test showed that the best treatment was found at treatment D (21 L : 3 D) with a mean value of length growth was 1,4 cm, weight growth was 0,07 g, specific growth rate was 0,30%/hari, long diversity coefficient was 1,83%, and survival rate was 89,33%. Keywords : Osteochilus kappeni, photoperiod, growth