Background and Aim: The standard chemoradiotherapy (CRT) protocol in head and neck cancers (HNC) consists of three cycles of high-dose cisplatin every three weeks. This study compared the acute toxicity profiles of these two concomitant CRT protocols in squamous cell carcinoma of the head and neck. Methods and Materials: 89 locally advanced head and neck cancers (HNC) patients’ candidate for CRT randomly assigned into two groups. Forty-seven patients to arm A (40 mg/m2 weekly cisplatin) and 42 patients to arm B (100mg/m2 triweekly cisplatin). According to National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 4.0, weekly assessment and grading of acute toxicities were done. Result: Our results did not show any statistically significant difference between the rate of treatment interruption and acute hematologic and non-hematologic toxicity profiles of the two schedules of cisplatin administration. Only there was a trend of more grade≥3 mucositis in the weekly cisplatin arm, but the difference was not significance. Conclusion: in terms of acute treatment toxicity the weekly administration of cisplatin concomitant with RT has the similar objective result with the triweekly schedule. However, because we did not assess the locoregional recurrence-free survival (LRFS) and overall survival (OS) in this trial, thus, we cannot suggest that weekly cisplatin CRT can be the alternative protocol for the standard triweekly schedule.