Hygiene can be defined as the science of preventive medicine and the preservation of health, the conditions of life which have an impact on health and on measures to prevent the disease. The main objective of maintaining personal hygiene is the preservation of health of the individual, collective and all people in the world. Proper and regular hygiene is a simple and inexpensive way to prevent the spread of many infectious diseases that can be transmitted by unclean hands, clothing, footwear and other means. Therefore, the aim of this graduation thesis was to explore whether the fourth graders have sufficiently developed personal hygienic habits, do they know why personal hygiene is important and is there a difference between boys and girls in hygiene maintenance. The study was conducted in the period March-June 2016. 80 fourth graders of primary school Marjan in Split took part in the study. A detailed analysis of the data showed that fourth-grade students do not have well-developed habits of personal hygiene. Also, the average level of development of hygienic habits is not statistically different regarding to the gender. For most of the students there is still much space for further education and improvement of the implementation of basic hygiene practices. Since personal hygiene is one of the most basic and easiest ways to prevent the spread of many infectious diseases and early school age appropriate time to adopt hygienic habits, these data should be an incentive for further engagement in the development of personal hygiene of children. An attitude and hygiene principle of the grown man largely depends of habits conducted in the childhood. Therefore, the special role is given to parents and teachers, who should be example for children to raise awareness about health, creating positive hygiene practices and their regular and proper implementation.