Abstrak: Tujuan penelitian ini adalah untuk mentetahui karakteristik SMA dan SMK di Medan. Karakteristik yang diteliti adalah: neuroticism, extraversion, keterbukaan, keramahan, dan hati nurani. Dengan penelitian ini kita mendapatkan data perbedaan karakter di SMA dan SMK siswa. Mendapatkan perbedaan karakter antara pria dan wanita dalam setiap kelompok sekolah. Penelitian ini di SMA dan SMK di Medan, 2008. Sampel penelitian 600 siswa. Metode Penelitian kuantitatif. Data diperoleh melalui kuesioner. Kuesioner dicoba dengan nilai koefisien reliabilitas (r=0,875). Hasil penelitian adalah: (1) Karakteristik siswa SMA (Neuroticsm, extraversion, keterbukaan, keramahan, dan hati nurani) sudah cukup dan kategori tinggi, (2) Karakteristik siswa SMK (Neuroticsm, extraversion, keterbukaan, keramahan, dan hati nurani) cukup tinggi dan kategori; (3) Para siswa perempuan SMA lebih tinggi hati nurani daripada siswa laki-laki; (4) Neuroticsm, extraversion, keterbukaan, dan keramahan antara siswa laki-laki secara signifikan tidak berbeda dengan siswa perempuan di SMA; (5) Neuroticsm, extraversion, keterbukaan, keramahan, dan conscientiousness antara mahasiswa laki-laki secara signifikan tidak berbeda dengan siswa perempuan di SMK. Kata kunci : karakteristik siswa, SMA, SMK. Abstract: This research was aimed to: investigate the Senior High School Studen’t Characteristic in Medan. The characteristic which investigated are: neuroticism, extraversion, openness, agreeableness, and conscientiousness. By this research we can get the accurate data that describe the differences of characters in SMA and SMK students. And then we can get the differences of characters among the male and female in each group of school. This research was taking place in SMA and SMK in Medan, 2008. The sample of this research is 600 pupils. The research was taken in the quantitative method. The data that we have got from the questioner. Questioner has been tried with the value of reliability coefficient (r=0,875). The results of the research are: (1) The SMA Studen’t Characteristic in Medan (Neuroticsm, extraversion, openness, agreeableness, and conscientiousness) is enough and high categories; (2) The SMK Student Characteristic in Medan (Neuroticsm, extraversion, openness, agreeableness, and conscientiousness) is enough and high categories; (3) The female SMA students are more conscientiousness than male students; (4) Neuroticsm, extraversion, openness, and agreeableness between male students significantly is not different with female students in SMA; (5) Neuroticsm, extraversion, openness, agreeableness, and conscientiousness between male students significantly is not different with female students in SMK. Keywords: characteristics of students, SMA, SMK