Bibliometrics and content analysis approaches were adopted in this study to review the papers issued in Journal of Library and Information Sciences from 1999 to 2020 to draw the landscape of library and information science studies, including research population, research subjects, research approaches and theories used. The results showed the growth of the research population, but the high percentage of one-time authors who lacked sustainable research efforts. Classical LIS topics, such as information behavior and information organization with mixed and newly developed approaches were the center of research. Research evaluation by bibliometrics approach expanded the scope of LIS studies. The presentation of theory linkage appeared limited, but increased in later published papers.