Karang Taruna Sendangmulyo is one of the youth organizations in Tembalang District, Semarang City. Based on the motivation of the village heads, this organization is directed to have an active role in accelerating the integrated waste management program launched by the local government. Manajemen of vegetable and fruit waste is a priority because of its great potential with the existence of traditional markets and the vegetable and fruit traders in this area. The purpose of this activity is to maximize the active role of Karang Taruna in managing profit-oriented waste. Waste management that is suitable for this condition is processing vegetable and fruit waste into liquid organic fertilizer (LOF) using fermentation techniques. The method of implementing this service is by explaining the innovation of waste fermentation techniques using a composter, demonstrations followed by implementation, as well as designing a marketing strategy. From the results of this activity, there was an increase in the knowledge, understanding, and skills of participants in making LOF using fermentation techniques. LOF produced has nutrient quality by the quality standards of liquid organic fertilizer as listed in the attachment of the Minister of Agriculture Number. 70/Permentan/SR.140/10/2019, so it is marketable. The initial strategy in marketing was to display LOF packaged in a bottle labeled by Karang Taruna. Promotional efforts are carried out through residents and women's organizations, as well as meeting forums which are often held at the village and sub-district levels. --- Karang taruna Sendangmulyo adalah salah satu organisasi pemuda di Kecamatan Tembalang Kota Semarang. Atas motivasi lurah desa, organisasi ini diarahkan untuk berperan aktif dalam percepatan program pengelolaan sampah terpadu yang dicanangkan pemerintah setempat. Pengelolaan limbah sayuran dan buah-buahan menjadi prioritas karena potensinya yang besar dengan keberadaan pasar tradisional serta banyaknya pedagang sayur dan buah di wilayah ini. Pengelolaan limbah yang cocok adalah mengolah limbah sayuran dan buah menjadi pupuk organik cair (POC) menggunakan teknik fermentasi. Tujuannya adalah memaksimalkan peran aktif karang taruna dalam mengelola sampah berorientasi profit. Adapun pelaksanaan pengabdian menggunakan metode partisipatif meliputi tahap paparan tentang teknik fermentasi limbah menggunakan komposter, demonstrasi dilanjutkan implementasi, serta merancang strategi pemasaran. Dari kegiatan ini dapat disimpulkan bahwa pelatihan pengolahan sampah organik yang dilakukan berhasil meningkatkan pengetahuan dan ketrampilan anggota Karang taruna Sendangmulyo dalam pembuatan POC dengan teknik fermentasi. Hasil implementasi pelatihan pembuatan POC menunjukkan keberhasilan 100%, terbukti dengan hasil analisis laboratorium menunjukkan kualitas POC memenuhi syarat unsur hara sesuai dengan standar mutu pupuk organik cair (Permentan Nomor 70/Permentan/SR.140/10/2019). Strategi pemasaran produk ditindaklanjuti dengan keseriusan kelompok Karang Taruna mewujudkan desain kemasan produk dan hasil analisis kualitas yang dicantumkan dalam label botol kemasan agar layak dipasarkan.