Abstract Lemna minor is a water plant that is easily obtained and has a good nutrient content that is high in protein. High protein for livestock can be used for production purposes. The study aims to determine the effect of administration of lemna minor on fat content, specific gravity, and dry matter without fat milk of friesien holstein dairy cows. The object of the study was 20 second-to-four-month FH lactating cows in the Dairy Farmer Group of Kp Tanggung Renteng Village, Pamegatan Village, Cikajang District, Garut Regency, West Java Province, then kept for 60 days and given feed according to treatment, namely R0 = Grass 60% + Concentrate 40%, R1 = 50% Grass + 40% Concentrate + 10% wet Lemna, R2 = 60% Grass + 37% Concentrate + 3% Dry Lemna, R3 = 50% Grass + 37% Concentrate + 10% Wet Lemna + 3% Dry Lemna, R4 = Grass 45% + Concentrate 38% + Wet Lemna 15% + Dry Lemna 2%. The results showed that the effect of administering lemna minor did not affect on fat content, specific gravity, and dry matter without milk fat. The conclusion that administration of lemna minor in dairy cattle feed cannot increase fat content, specific gravity, and dry ingredients without fat Holstein friesien milk. Keywords : lemna minor, fat content, density, solid non fat Abstrak Lemna minor merupakan tanaman air yang mudah diperoleh dan memiliki kandungan nutrient yang baik yaitu protein tinggi. Protein yang tinggi bagi ternak dapat dimanfaatkan untuk meningkatkan produksi. Penelitian bertujuan untuk mengetahui pengaruh pemberian lemna minor terhadap kadar lemak, berat jenis, dan bahan kering tanpa lemak susu sapi perah friesien holstein. Objek penelitian yang digunakan adalah 20 ekor sapi FH laktasi kedua sampai empat bulan di Kelompok Peternak Sapi Perah Kp Tanggung Renteng Desa Pamegatan Kecamatan Cikajang Kabupaten Garut Provinsi Jawa Barat kemudian dipelihara selama 60 hari dan diberikan pakan sesuai dengan perlakuan yaitu R0= Rumput 60% + Konsentrat 40%, R1= Rumput 50% + Konsentrat 40% + Lemna basah 10%, R2= Rumput 60% + Konsentrat 37% + Lemna Kering 3%, R3= Rumput 50% + Konsentrat 37% + Lemna Basah 10% + 3% Lemna Kering, R4= Rumput 45% + Konsentrat 38% + lemna basah 15% + Lemna Kering 2%. Hasil penelitian menunjukkan bahwa pengaruh pemberian lemna minor tidak berpengaruh terhadap (P>0,05) kadar lemak, berat jenis, dan bahan kering tanpa lemak susu. Kesimpulan bahwa pemberian lemna minor dalam pakan sapi perah tidak dapat meningkatkan kandungan lemak, berat jenis, dan bahan kering tanpa lemak susu friesien Holstein. Kata kunci : lemna minor, kadar lemak, berat jenis, bahan kering tanpa lemak