Perilaku seksual dapat beresiko terjadinya Penyakit menular seksual (PMS) bila melakukan hubungan seksual dengan berganti-ganti pasangan baik melalui vagina, oral, maupun anal. Kasus Penyakit Menular Seksual yang ditemukan pada Tenaga Kerja Bongkar Muat Pelabuhan yang pernah menderita yaitu sebanyak 24 orang.Tujuan penelitian ini untuk mengetahui perilaku seksual Tenaga Kerja Bongkar Muat Pelabuhan yang pernah menderita penyakit menular seksual di Kabupaten Banggai. Lokasi penelitian dilakukan di kabupaten Banggai pada tahun 2016. Waktu penelitian dilaksanakan pada bulan Oktober-November tahun 2016. Penelitian ini menggunakan metode kualitatif dengan pendekatan wawancara mendalam dan direkam. Jumlah informan 17 orang, yang tidak bersedia diwawancara sebanyak 6 orang dan 1 orang telah meninggal dunia informan kunci sebanyak 2 orang. Hasil penelitian menunjukkan bahwa informan sudah melakukan perilaku seksual yang beresiko yaitu perilaku seksual yang dilakukan secara berganti-gantian pasangan serta tidak menggunakan alat kontrasepsi dan terakhir kali informan melakukan hubungan seksual dengan wanita yang beresiko yaitu wanita pekerja seksual. Masyarakat diperlukan mendapatkan infomasi tentang perilaku-perilaku seksual yang beresiko pada kesehatan terutama tentang kesehatan reproduksi, sehingga kedepanyya mereka tidak akan mendapatkan penyakit yang dapat merugikan diri mereka sendiri. Sexual behavior can be at risk of sexually transmitted diseases (STDs) when having sexual intercourse by changing partners via vaginal, oral, or anal. Cases of sexually transmitted diseases were found in Port Loading and Unloading Workers who had suffered as many as 24 people. The purpose of this study was to determine the sexual behavior of Port Load Unloading Workers who had suffered from sexually transmitted diseases in Banggai District. The research location was conducted in Banggai district in 2016. The research was conducted in October-November 2016. This study used a qualitative method with in-depth interviews and recorded approaches. There were 17 informants, 6 of whom were unwilling to be interviewed and 2 of them had died as key informants. The results showed that the informants had carried out at risk sexual behavior that is sexual behavior that was carried out alternately-changing partners and did not use contraception and the last time the informant had sexual relations with women who were at risk namely women who were sex workers. Communities are required to get information about sexual behaviors that pose a risk to health, especially about reproductive health, so that in the future they will not get diseases that can harm themselves.