Lesbian, gay, bisexual, transgender, and queer (LGBTQ) people constitute a vulnerable population that requires research about their needs, representations, and challenges. Among the variant research methods, ethnography is particularly effective in understanding participants and their lived experience. The development of information and communication technologies has transformed traditional ethnography research and contributed to the emergence of online ethnography research that holds potential for studying vulnerable populations (e.g., LGBTQ people) and relevant topics. We propose a systematic review to explore how researchers have considered and addressed ethical and methodological issues in LGBTQ-focused online ethnography research. We used the core collection of the Web of Science to search for relevant literature. We crafted the search query based on studies of LGBTQ populations, online ethnography studies, and other data sources like the Homosaurus vocabulary. Two groups of search terms were compiled and used in combination, including population-related terms (e.g., “queer”, “LGB*”, “GLB*”, and “sexual minorit*”) and method-related terms (e.g., “online ethnograph*”, “netnograph*”, “digital ethnograph*”, and “virtual ethnograph*”). In this review, we focus on empirical journal articles using any type or variant of online ethnography to investigate LGBTQ-focused topics. The eligible articles may include LGBTQ people as participants or stakeholders (e.g., LGBTQ staff), or analyze LGBTQ-related content (e.g., YouTube videos). Most importantly, we will analyze the ethical concerns (e.g., informed consent, power imbalance, cultural sensitivity, and beneficence and justice) and methodological aspects (e.g., research design, sampling, recruitment, data collection, data analysis, and roles of LGBTQ people) of these studies.