Background Since the beginning of the century, dietary patterns have been changing rapidly due to evolving lifestyles, restaurants that cater to dietary restrictions, etc. As a result, populations started consuming a large amount of salt in their diets. Years of research have found that high salt intake is strongly related to many serious health problems like hypertension and cardiovascular diseases. This study's objective is to evaluate knowledge, attitudes, and practices regarding dietary salt intake among medical students at King Abdulaziz University (KAU) in Jeddah, Saudi Arabia, and to identify barriers and concerns related to optimum dietary sodium intake. Method A cross-sectional study done at KAU among 310 students using an online questionnaire included items to assess their knowledge, attitudes, and practices related to dietary salt intake. There were 24 questions to assess knowledge, six questions to assess attitude, and eight questions to assess practice. Results The mean age of the participants was 21.52 ± 1.94 years; 180 of the 57.5% were female. A score of "1" was given to the right answer for knowledge, positive attitude, and correct practice. The mean knowledge, attitudes, and practices scores were 16.99 ± 3.8, 3.03 ± 1.46, and 2.13 ± 1.34, respectively. The percentage of poor, fair, and good knowledge levels regarding dietary salt intake among studied students was 72:23%, 210:67.1%, and 31:9.9%. While the prevalence of negative, fair, and positive attitudes was 111:35.5%, 141:45%, and 161:9.5%. As for practice level, none of the students had good practice, while 263:84% and 50:16% had poor and fair practice, respectively. Conclusion In conclusion, the majority of students were aware that a high-salt diet can result in serious health issues. They were also uncertain of whether their salt intake was extremely high or not, which is consistent with thefact that they were ignorant of the daily salt intake guidelines. The findings in our study can stand as a reference point for salt-related knowledge, attitude, and practice (KAP) studies to help further future research in Saudi Arabia and other countries. Multi-sector coordination between the food suppliers, health agencies, and government is necessary to increase public awareness, decrease the salt content of food, and lower individual salt consumption in Saudi Arabia.