ABSTRAK Telah dilakukan penelitian tentang efek pemberian ekstrak etanol kayu manis (Cinnamomum burmannii Ness ex BI.) terhadap kadar ureum dan kreatinin darah tikus (Rattus novergicus). Penelitian ini bertujuan untuk mengetahui pengaruh pemberian ekstrak kayu manis terhadap kadar ureum dan kreatinin darah tikus. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL). Tikus dibagi menjadi 4 perlakuan dengan 5 ulangan pada setiap perlakuan. Perlakuan 0 (P0) adalah tikus yang diberi pellet, air minum dan carboxymethyl cellulose (CMC) 0,5%. Perlakuan I (P1) merupakan tikus diberi perlakuan pellet, air minum dan ekstrak kayu manis dengan dosis 200 mg/kgBB, perlakuan II (P2) tikus diberi perlakuan pellet, air minum dan ekstrak kayu manis dengan dosis 400 mg/kgBB, serta perlakuan III (P3) tikus diberikan pellet, air minum dan ekstrak kayu manis dengan dosis 800 mg/kgBB. Pemberian eksrak kayu manis dilakukan selama 14 hari, pada hari ke-15 dilakukan pengambilan sampel darah melalui vena orbitalis untuk pemeriksaan kadar ureum dan kreatinin darah tikus. Data dianalisis dengan menggunakan Analisis of Varian (ANOVA). Hasil penelitian menunjukkan bahwa pakan mempengaruhi kadar ureum tikus dan kadar kreatinin semua perlakuan normal. Kata kunci: Ureum, Kreatinin, Rattus novergicus, Cinnamomum burmannii Ness ex BI.   ABSTRACT This research was conducted about the effects of giving cinnamon ethanol extract (Cinnamomum burmannii Ness ex BI.) on blood ureum and creatinine levels of rats (Rattus novergicus). This research was aimed to determine the effect of giving cinnamon extract to blood ureum and creatinine levels of rats. This research used Completely Randomized Design (RAL). Rats were divided into 4 treatments with 5 replications on each treatment. Treatment 0 (P0) was given with pellet, drinking water and carboxymethyl cellulose (CMC) rats 0,5%. Treatment I (P1) was treated with pellet, drinking water and cinnamon extract at dose 200 mg / kgBW, treatment II (P2) rats were treated with pellet, drinking water and cinnamon extract at dose 400 mg / kgBW, and treatment III (P3) rats were treated with pellet, drinking water and cinnamon extract at dose 800 mg / kgBW. The cinnamon extract was given for 14 days, on the 15th day, blood sample was taken through the orbital vein for examining the blood ureum and creatinine levels of rat. Data were analyzed using Analysis of Variant (ANOVA). The results showed that feed affects rat ureum and creatinine levels of all normal treatments. Keywords: Ureum, Creatinine, Rattus novergicus, Cinnamomum burmannii Ness ex BI.