We report on the clinical observation of a girl patient with few signs of cri-du-chat syndrome. The chromosomal analysis in lymphocyte culture showed 46,XX,del(5)(p15.3) in 38% of cells. Psychological tests revealed motor, perceptive and visual-spatial problems, as well as immaturity and emotional dependence. The phoniatric evaluation showed poor vocabulary, difficulty with repeating words or numbers in sequence, and better receptive than expressive language. The spectrographic measurements showed disturbance of fundamental frequency (F0) in vocal pronunciation. The anatomic findings of the laryngoscopic evaluation were normal, indicating that the voice and speech problems were functional disorders. The present case revealed moderate clinical signs and vocal disturbance associated with a low percentage of 5p- cells and the breakpoint at 5p15.3. The short terminal deletion with a possible loss of the critical region for cat-like cry and the presence of a normal cell line, explain the cry not so typical at birth (weak but not high-pitched), the intermediate values of F0, and the moderate mental retardation. This case is compared with other mosaic 5p- patients reported in the literature.