The predominant symptoms of trisomy 14 mosaicism are prenatal and postnatal growth failure, ear abnormalities, congenital heart disease, developmental delay, and genitourinary abnormalities. Maternal uniparental disomy of chromosome 14 (upd(14)mat) presents discernible clinical features such as prenatal and postnatal growth failure, hypotonia, precocious puberty, and obesity. Given the small number of previously reported patients with a combination of trisomy 14 mosaicism and upd(14)mat, the detailed clinical features of these patients remain to be elucidated. Here we report a severely short-statured girl with feeding difficulties and failure to thrive, ear abnormalities, deafness, small hands, and developmental delay. Karyotyping, FISH analysis, methylation analysis, and microsatellite marker analysis using her leukocytes and buccal cells showed that she had a combination of trisomy 14 mosaicism and upd(14)mat. Furthermore, a comparison of the clinical features of this patient with those of previously reported patients with genetic anomalies including the combination of trisomy 14 mosaicism and upd(14)mat or upd(14)mat suggested that the severe short stature observed in patients with a combination of trisomy 14 mosaicism and upd(14)mat stemmed from the synergic effect of these two events. In severely short-statured patients with trisomy 14 mosaicism, we should be aware of the possible coexistence of upd(14)mat.