PURPOSES: to investigate the occurrence of lisping during fricative sounds produced by children with malocclusal and to analyze the influence of the syllabic context of the fricative in the perceptual judgment of lisping. METHOD: this prospective study involved auditory perceptual identification of lisping by three experienced speech-language pathologists who judged 428 recorded words produced by 15 children (mean age of 5y1m). The words included alveolar and post-alveolar unvoiced fricative consonants, produced in initial word position followed by [i, a, u] vowels in the stressed position. Intra (almost perfect) and inter (total, 100%) judgments were obtained before analyzing the data. RESULTS: although all studied children presented lisping at least during one fricative production, it was identified in 25,23% of the recording analyzed words. A significant increase in lisping was observed for: (a) alveolar fricative in the initial word position (p <0.001), (b) alveolar fricative in the initial word position, in relation to the medial coda (p = 0.001) and (c) alveolar fricative in relation to post-alveolar fricative (p <0.001). There was no significant decrease in the lisping in relation to co-articulated vowels. CONCLUSION: the occurrence of lisping depends on the syllabic context (with more occurrence in alveolar fricative in initial word position), therefore, this context should be considered for clinical and research purposes.