The current study was designed to investigate the type of handwriting problems in elementary school as well as their frequency. The research method was descriptive in the first phase and quasi experimental (pretestpost-test without a control group) in the second phase. Three-hundred students (150 male and 150 female) were selected by means of cluster sampling methods. A reading inventory and the alphabet cards developed by the researcher were used to assess reading problems. To analyse data, descriptive statistics (e. g. frequency of problem), in the first phase and inferential statistics, U-Mann Whitney, were used in the second phase. The results indicated that most participants had problems in distortion (Jee, Chee, Hea, Kha, Sad, Zad, Ta-Za, Ain-Ghayn, Fa, and Ghai). Most of the problems in graphic were associated with distortions and deforming of the letters. These problems have been observed in male and female students. However, male students ( =11/52) had more problems than female students. The least amount of the problems was associated with third kind of problem that is omission of one or several dots. Among different types of distortions, letter distortion was the highest and reversing letters had the least frequency. It is worthy to mention that, after five months and teaching to write letters in interventional training, the amount of this mistake in both sexes has decreased. The rate of changes after intervention in the left-handed persons was higher. However, the average of errors in right-handed people was lower than in the left-handed group before and after intervention.