Purpose/Objectives/Research/Focus of Study: This qualitative study investigated online instructors' perceptions of cultural diversity in the online classroom and the challenges that instructors of online courses encounter in their efforts to incorporate cultural diversity and multicultural learning contents in the online learning environment. An associated goal of the study was to explore the instructional strategies that online instructors use to create conducive online learning environments that value cultural differences as well as the educational experiences of students in online classrooms. Population/Participants/Subjects: Fifty full-time instructors of online courses from three universities in the northeastern part of the United States participated in the study. The participants included Clinical Professors of Practice (n = 4), Assistant Professors (n = 18), Associate Professors (n = 16), and Full Professors (n = 12). There were 23 females and 27 males from different academic disciplines and cultural backgrounds. Research Questions: Unlike many previous studies, this study sought to uncover online instructors' perceptions of cultural diversity in the online classroom, the pedagogical strategies they employ to address issues related to cultural diversity in online learning, and the challenges they encounter in their efforts to promote cultural diversity and incorporate multicultural learning content into their online instruction. Specifically, this study explored the following research questions: (1) How do instructors of online courses perceive cultural diversity and the impact of cultural diversity in online learning? (2) What instructional strategies do instructors of online courses use to address issues related to cultural diversity in online learning environments? (3) What challenges do instructors of online courses encounter in their efforts to promote cultural diversity and multicultural learning content in online environments? Research Design: This study employed qualitative research design using semi-structured interviews and content analysis to explore instructors' perceptions of cultural diversity in online learning as well as the challenges encountered by instructors of online courses in their efforts to promote cultural diversity and incorporate multicultural learning content into their online instruction. The qualitative research design was chosen because it allowed the researchers to collect and analyze data about the instructors' perceptions of cultural diversity based on their own voices, with the aim of producing conceptual explanations of the types of instructional strategies that instructors use to promote cultural diversity in online education and the challenges they encountered in the online classroom (Ashong & Commander, 2012; Jung & Gunawardena, 2014). Findings/Results: The findings of the study pointed to four themes, namely that: (1) differential perceptions of cultural diversity exist among instructors of online courses; (2) perceptions of cultural diversity depend on the academic disciplines taught by instructors; (3) a variety of instructional strategies--collaborative online learning activities, incorporating multicultural learning activities and global learning content, using cultural awareness activities, addressing the impact of multicultural education--support cultural diversity in the online environment; and (4) there are significant challenges associated with promoting cultural diversity in online teaching and learning. Conclusions and Recommendations: Findings revealed that the majority of the instructors view cultural diversity as the recognition of students' cultural differences within the online learning environment, the ability of instructors to infuse multicultural content into their curriculum, and the capacity of instructors to use a variety of strategies to facilitate instructional delivery to meet the needs of students from diverse cultural backgrounds who study in the online environment. Findings also suggested that instructors' perceptions of cultural diversity in the online setting vary depending on their teaching discipline and academic preparation. Specifically, instructors in education, social sciences, and engineering demonstrated a good understanding and awareness of cultural diversity. They also felt the need to provide support that enhanced the learning experiences of diverse student populations in the online environment. On the contrary, instructors in the physical sciences did not demonstrate such a good understanding of cultural diversity and showed little knowledge of ways to incorporate multicultural learning content to help diverse student populations achieve academic success in online education. In light of the findings from this study, the researchers recommend that online instructors and instructional designers work toward enhancing their knowledge of cultural diversity and toward incorporating multicultural resources in their curricula to support diverse student populations (including those with learning disabilities) in online education.