Writing is a complex linguistic-cognitive process. It is influential both in the educational and in the non-educational social environment. The most important turning point in children's learning of alphabetic writing is considered to be the development of the idea that graphemes represent spoken sounds. However, not all languages from the alphabetic orthographic system are equally transparent. The presence of inconsistencies and irregularities in language can slow down and hinder the development of writing. Despite the preserved cognition, children with language difficulties may have problems with all language components - phonology, morphology, syntax, semantics and pragmatics. Phonotactics is a branch of phonology that determines possible combinations of phonemes in a particular language. Phonotactic limitations are already a well-established concept in oral language research, so the aim of this paper was to link phonotactics with written language, determine how phonotactic factors affect the occurrence of errors in written productions of children with language difficulties and finally describe their learning mechanism. Although research on this topic is scarce, a review of the literature showed that children made the most mistakes in writing consonant clusters, longer words, and less frequent graphemes. Despite the fact that pseudo-words follow the phonotactic rules of a certain language, results showed no significant difference in number of errors that children with language difficulties made in spelling of pseudo-words and irregular words, while their least problem was spelling regular words. Children with language impairment produce phonologically unacceptable errors. Knowledge of graphemes at the end of the first grade is at a very poor level, during the initial mapping of graphemes they do not use phonotactic information. In general, they make insufficient use of the linguistic information present during grapheme writing. But over time, they learn and improve in their writing. Given that the errors produced were quantitatively but not qualitatively different from those produced by children of orderly development, emphasis is placed on the need for reinforced explicit instructions as early as possible.