Background: Anaemia is one of the most significant health problems among children in the world. Detecting anaemia before the symptoms begin to arise will help in limiting the magnitude of this problem. Anaemia is generally recognized as the greatest nutritional problem among children and adolescents. Aims of the Study: This study aims to measure the prevalence, severity, and risk factors of anaemia in primary school children of Alabnaa primary schools, Tabuk city, Saudi Arabia, in the academic year of 2018-2019. Methods: The present study is a cross-sectional one, carried out at Alabnaa primary schools at Tabuk city, Saudi Arabia with total coverage of all the students, who were enrolled in the academic year of 2018-2019. The data was collected via a pre-tested questionnaire, designed to meeting study objectives. The total number of the sampled students was 4158, they have undergone, personal interviews and filling out the questionnaire. General examination including observation of the general condition, and pallor, measuring of pulse, weight, and height, chest, heart, and abdominal examination was done to detect any gross abnormality. Then every student was subjected to measuring the blood HB% by Sahle’s method. Students having haemoglobin level less than 70% [cut off point] considered anaemic. Results: The overall prevalence of anaemia among the studied students was 15.6%. Among the anaemic children, 340 (7.6%) had mild anaemia, 308 (7.4%) had moderate anaemia, and 3 (0.07%) had severe anaemia. There was a significant relationship between haemoglobin level and some socio-demographic characteristics and dietary practices of the studied children. Conclusion: This study has revealed that the prevalence of anaemia in children is high and several steps are still needed to increase public awareness about the complications of anaemia, good nutritional habits, iron sources, and prevention of nutritional anaemia.