Latar belakang: Kecamatan Tembalang, dengan populasi mahasiswa yang besar, merupakan penyumbang sampah terbanyak kedua di Kota Semarang pada tahun 2024 mencapai 49.367,454 ton/tahun. Peningkatan volume sampah ini sejalan dengan pertumbuhan populasi serta konsumsi masyarakat. Pemilahan sampah dari sumbernya menjadi langkah utama untuk mengatasi masalah ini. Penelitian ini bertujuan untuk menganalisis faktor pengetahuan, sikap, persepsi sarana prasarana dan persepsi tokoh masyarakat dengan praktik mahasiswa dalam pemilahan sampah.Metode: Penelitian ini mengadopsi pendekatan observasional analitik dengan rancangan studi cross-sectional, melibatkan 130 mahasiswa aktif jenjang D3, D4, dan S1 dari tiga universitas di Kecamatan Tembalang, 6 petugas pengangkut sampah, dan 6 tokoh masyarakat di wilayah Kecamatan Tembalang. Data dikumpulkan melalui wawancara menggunakan Google Forms pada November – Desember 2024, dengan teknik pengambilan sampel accidental dan purposive sampling. Variabel yang diteliti meliputi pengetahuan, sikap, persepsi sarana prasarana dan dukungan tokoh masyarakat, serta praktik pemilahan sampah. Data dianalisis secara univariat dan bivariat menggunakan uji Chi-Square.Hasil: Responden yang memiliki pengetahuan kurang baik (50,8%), sikap negatif (63,1%), persepsi sarana prasarana kurang memadai (63,8%), persepsi dukungan tokoh masyarakat rendah (71,5%), dan praktik pemilahan sampah kurang baik (71,5%), sarana prasarana kurang memadai (66,7%), dan dukungan tokoh masyarakat rendah (50%). Tidak ada hubungan antara pengetahuan dengan praktik (p=0,096), ada hubungan antara sikap (p=0,001), persepsi sarana prasarana (p=0,013), persepsi dukungan tokoh masyarakat (p=0,001) dengan praktik pemilahan sampah di Kecamatan Tembalang.Simpulan: Pengetahuan tidak berhubungan dengan praktik pemilahan sampah tetapi sikap, persepsi sarana prasarana dan persepsi dukungan tokoh masyarakat memiliki hubungan dengan praktik pemilahan sampah pada mahasiswa di Kecamatan Tembalang. ABSTRACT Title: Analysis Of Knowledge, Attitudes, Perceptions Of Infrastructure And Community Leaders With Student’s Waste Sorting Practices In TembalangBackground: Tembalang, with its large student population, is the second largest contributor of waste in Semarang City in 2024, reaching 49,367.454 tons/year. The increase in waste volume is in line with population growth and consumption. Waste sorting from the source is the primary step in overcoming this problem. This study analyzes the factors of knowledge, attitude, infrastructure perception, and community leader support on waste sorting practices among students.Method: Employing an analytical observational approach with a cross-sectional design, the study involved 130 active students at D3, D4, and S1 levels from three universities in Tembalang, 6 waste collectors, and 6 community leaders. Data were collected via direct interviews using Google Forms from November to December 2024. Sampling techniques included accidental and purposive sampling. Variables measured were knowledge, attitude, infrastructure perception, community leader support perception, and waste sorting practices. Data were analyzed univariately and bivariately using the Chi-Square test.Result: Respondents had poor knowledge (50.8%), negative attitudes (63.1%), perceptions of inadequate infrastructure (63.8%), perceptions of low community leader support (71.5%), inadequate infrastructure (66.7%), and low community leader support (50%). While knowledge showed no relationship with practices (p=0.096), attitude (p=0.001), infrastructure perception (p=0.013), and community leader support perception (p=0.001) were significantly associated with waste sorting practices. Conclusion: Knowledge does not correlate with waste sorting practices, but attitudes, infrastructure perception, and community leader support significantly influence waste sorting practices among university students in Tembalang.