Objective Tonsillectomy is a common operation; however, there are controversial opinions regarding the posttonsillectomy diet. The aim of this study was to compare the effects of cold/liquid diet vs regular diet on posttonsillectomy pain and bleeding. Study Design Prospective randomized controlled trial. Setting Tertiary referral center. Subjects and Methods In total, 194 children who underwent tonsillectomy (with or without adenoidectomy) were randomly allocated into 2 groups. A total of 100 patients were allocated in the cold/liquid diet, and 94 patients were allocated in the regular diet group. Pain score was recorded for the first 7 days, and rate of hemorrhage was recorded for 10 days after surgery. Results The participants' age range was 3 to 17 years. The mean pain score level in the regular diet group after breakfast, lunch, and dinner was not statistically significant in comparison with the cold/liquid diet group. One patient in the regular diet group was admitted to the hospital due to secondary bleeding, but it stopped without any intervention. Conclusion Most otolaryngologists believe in dietary restrictions following tonsillectomy. However, there is much controversy regarding posttonsillectomy dietary advice in the literature. In addition, only a few randomized clinical trials have focused on this subject. We found that there was no difference between regular diet and cold/liquid diet in terms of posttonsillectomy pain and bleeding. Hence, we do not recommend a limited posttonsillectomy diet.