Penelitian ini bertujuan untuk mengetahui pengaruh pemberian ekstak kenikir terhadap kadar glukosa darah tikus putih dan mengetahui dosis efektif dari ekstrak kenikir dalam menurunkan kadar glukosa darah tikus putih. Penelitian ini merupakan penelitian eksperimen dengan rancangan acak lengkap (RAL). Populasi penelitian yaitu tikus putih galur wistar jantan. Sampel penelitian menggunakan 24 ekor tikus putih yang terbagi dalam 4 kelompok, yaitu kelompok kontrol dan tiga kelompok perlakuan yaitu 200 mg/kgBB, 300 mg/kgBB, dan 400 mg/kgBB. Data dianalisis menggunakan One Way Anova, apabila terdapat pengaruh nyata maka dilanjutkan dengan uji perbandingan Duncan’s Multiple Range Test (DMRT). Hasil penelitian menunjukkan bahwa variasi pemberian ekstrak daun kenikir berpengaruh sangat signifikan (P0.01) terhadap penurunan kadar glukosa darah tikus. Hasil uji DMRT menunjukkan bahwa terdapat pengaruh yang berbeda nyata antara kelompok kontrol dengan ketiga kelompok perlakuan lainnya. Dosis yang paling efektif dalam menurunkan kadar glukosa darah yaitu dosis 400 mg/kgBB dengan rata-rata kadar glukosa 99,73 mg/dl.Kata kunci: Ekstrak daun kenikir (Cosmos caudatus), kadar glukosa, tikus putih (Rattus norvegicus, L.)This study aimed to determine the effect of giving kenikir extract (Cosmos caudatus) on blood glucose levels of white rats with wistar strain (Rattus norvegicus, L) and to determine the effective dose of kenikir extract in lowering blood glucose levels in white rats. This study was an experimental study with a Completely Randomized Design (CRD). The research population was male wistar white rats. The research sample used 24 white rats which were divided into 4 groups, they were the control group, and three treatment groups, it was 200 mg/kgBW, 300 mg/kgBW, and 400 mg/kgBW. The data were analyzed using a one-way variant. Then, if there was a significant effect, then it was continued with the Duncan's Multiple Range Test (DMRT). The results of this study showed that the variation of giving kenikir leaf extract had a very significant effect (P0.01) on decreasing blood glucose levels in white rats. Then, the results of the DMRT test showed that there was a significantly different effect between the control group and the other three treatment groups. The most effective dose in lowering blood glucose levels was a dose of 400 mg/kgBW with an average glucose level of 99.73 mg/dl.Keywords: Kenikir leaf extract (Cosmos caudatus), glucose levels, white rats (Rattus norvegicus, L.)