The widespread misconception that tonsillectomy leads to a decrease in immunity may lead to fear and avoidance of the operation. This can result in a deterioration of the situation, such as sleep-related breathing issues, frequent infections, and an increase in complications. The current research was conducted to assess the awareness and perception with respect to the impact of tonsillectomy on the immune system and to assess the awareness and perception of the relationship between autoimmune diseases and tonsillectomy. This 6-month descriptive cross-sectional online questionnaire survey was conducted among individuals who were 18 years and above living in Abha city, Saudi Arabia. Out of the 800 study subjects, 104 (13%) had undergone tonsillectomy. Statistically significant associations were found between age group, education, income, and occupation among those who had undergone tonsillectomy. Multivariate logistic regression analysis showed that ages 18–30 years and 31–40 years (OR: 2.36, 95% CI: 1.18–4.71, and OR: 1.46, 95% CI: 0.53–3.97) and education levels of high school, bachelors, and above (OR: 8.30, 95% CI: 3.05–22.58 and OR: 10.89, 95% CI: 4.23–28.05) were found to be associated with tonsillectomy status of the subjects. On the contrary, income levels of 5000–9000 and >9000 (OR: 0.65, 95% CI: 0.36–1.17 and OR: 0.78, 95%CI: 0.42–1.42) and male gender (OR: 0.79, 95% CI: 0.52–1.19) were found to be associated with non-tonsillectomy status of subjects. Almost 36% of study subjects thought that tonsillectomy affects immunity. Only 18% of study subjects thought that there is a relationship between tonsillectomy and autoimmune diseases. About one-third of the respondents had received this information from community members and social media. A small number of study subjects relied on public awareness programs. Therefore, social media can play a vital role in the community to remove misconceptions regarding tonsillectomy and its effect on immunity and autoimmune disease. Further educational interventional studies are required to see the correction to the public perception of tonsillectomy and its effect on immunity and autoimmune diseases.