The study aims to explore the teaching behaviors of cross-country online tutors and the factors influencing teaching behaviors. The study adopts semi-structured interview as the research method. The research participants are seven cross-country online tutors in Taiwan- Korea Online Tutoring Service Program administered by National Chi Nan University. The research findings indicate that the tutors mainly adopt three teaching methods: didactic instruction, practicing instruction, and inquiry teaching. They conduct curriculum selection according to the achievement of teaching objectives, students' needs, interests, and ability, and the importance, breadth, depth, and accuracy of the content. The assessments are adopted during and after tutoring. The tutors interact with their students in a way similar to peer interaction and play more roles of teaching and professional development than those of consulting. Their teaching process contains preactive tasks - comprehension and transformation, and interactive tasks - instruction and evaluation, while postactive tasks - reflection and new comprehension are neglected. The study also concludes nine factors influencing cross-country online tutors' teaching behaviors. At the end of the article, several suggestions on cross-country online tutoring activities are proposed according to the researching findings.