Penelitian ini bertujuan untuk mengetahui dan mendapatkan jenis mulsa dan dosis pupuk organik yang tepat terhadap produksi tanaman semangka (Cucumis vulgaris Scard..). Penelitian ini telah dilaksanakan di lahan petani di Desa Tanah Lembak, Kec. Rambutan, Kab. Banyuasin Sumatera Selatan yang. Penelitian ini telah dilaksanakan dari bulan Mei sampai Agustus 2022. Penelitian ini menggunakan metode eksperimen dengan Rancangan Petak Terbagi (Split-plot design) terdiri dari 12 kombinasi perlakuan yang di ulang 3 kali. Adapun perlakuan yang dimaksud adalah sebagai berikut petak utama : jenis mulsa organik (M) yaitu M0 = tanpa mulsa ; M1 = mulsa alang-alang ; M2 = mulsa jerami padi ; M3 = mulsa plastik sedangkan anak petak : dosis pupuk kotoran sapi (D) yaitu D1=10 ton/ha ; D2 = 20 ton/ha ; D3= 30 ton/ha. Peubah yang diamati dalam penelitian ini adalah Diameter buah (cm), Panjang buah (cm), Berat buah pertanaman (kg) dan Berat buah perpetak (kg). Berdasarkan hasil penelitian menunjukkan bahwa secara tabulasi perlakuan kombinasi Secara tabulasi penggunaan jenis mulsa jerami padi dengan dosis pupuk pupuk kandang kotoran sapi 30 ton/ha memberikan hasil tertinggi terhadap produksi tanaman semangka per petak sebesar 49,87 atau setara dengan 66,49 ton/ha. This study aims to determine and obtain the right type of mulch and organic fertilizer dosage for the production of watermelon plants (Cucumis vulgaris Scard..). This research was carried out on farmer's land in Tanah Lembak Village, Kec. Rambutan, Kab. Banyuasin, South Sumatra. This research was conducted from May to August 2022. This research used an experimental method with a Split-plot design consisting of 12 treatment combinations which were repeated 3 times. The treatment in question is as follows main plot: type of organic mulch (M), namely M0 = without mulch; M1 = reed mulch; M2 = rice straw mulch; M3 = plastic mulch while subplots: dose of cow manure (D), namely D1 = 10 tons/ha ; D2 = 20 tonnes/ha ; D3 = 30 tonnes/ha. The variables observed in this study were fruit diameter (cm), fruit length (cm), fruit weight per plot (kg) and fruit weight per plot (kg). Based on the results of the study, it was shown that tabulated combination treatment tabulated the use of rice straw mulch with a dose of 30 tons/ha of cow dung manure gave the highest yield of watermelon plant production per plot of 49.87 or the equivalent of 66.49 tons/ha.