Writing is considered one of the most complex linguistic activities, as it requires the coordinated execution of a large number of cognitive activities (Alamargot and Chanquoy, 2001). According to the Model of Cognitive Processes (Hayes and Flower, 1980), writing consists of three basic (meta)cognitive processes: planning, translating, and reviewing. It is assumed that all three processes are controlled by the working memory, and compete for its limited resources during text composition (Olive et al., 2002). The dynamics of these processes can be described by their temporal organization and cognitive demands. Advances in technology have made it possible to measure these concepts using various computer software and technologies. The aim of this study was to describe the dynamics of the cognitive processes underlying writing in adult deaf people and to compare them with those of hearing people. Despite advances in hearing aid technology, the period of lack of access to auditory stimuli, that deaf children go through before receiving hearing aids has a negative impact on their spoken language development (Mayer and Trezek, 2019). The study involved 10 deaf and 10 hearing respondents who were matched in terms of age, gender, level of education, and general cognitive ability. The dynamics of the cognitive processes underlying writing were examined using the triple task technique (Kellogg, 1987). The written texts were then analysed using objective measures of text quality. The results showed that deaf and hearing participants did not differ significantly in the distribution and cognitive demands of planning, translating, and reviewing when writing. As far as the written product is concerned, there are differences in the number of grammatical errors. Deaf participants wrote texts with less grammatical accuracy.