In order to elucidate their cranial and facial morphological features, frontal and lateral cephometric analysis was made of parents of 86 children with cleft lip with or without cleft palate [CL (P)] and 14 children with cleft palate (CP). Similar analysis was made of 30 control male and female volunteers who demonstrated no maxillofacial anormalies and had no blood relatives affected by CL(P) or CP. In addition, discriminative analysis was performed. Results (1) Maximum cranial breadth values in the 4 parent groups, both father groups [CL(P)-F, CP-F] and mother groups [CL(P)-M, CP-M] were lower than those in controls. Differences were significant in the CP-F and CP-M groups. The shapes and sizes of the cranial base, however, in all parent groups showed no distinct difference from those in the control group. (2) Inner canthal distance and maximum piriform aperture breadth in all parent groups and outer canthal distance, zygoma breadth, and maxillary alveolar base breadth in the CL(P)-F, CL(P)-M, and CP-M groups were all greater than those in controls. The differences were significant in the case of inner canthal distance and maximum piriform aperture breadth in the CL(P)-F group and in both inner and outer canthal distances and maximum piriform aperture breadth in the CL(P)-M group. (3) SNA angle in all parent groups was slightly greater, but occlusal plane angle and maxillary incisor angle were smaller than those in the control group. Significant difference was noted in occlusal plane angle in the CL(P)-F group. In all parent groups, depth values at various upper facial points in the lateral aspect of hard tissue tended to be greater and height values smaller than those of the control group. (4) In all parent groups, upper facial height, upper labial thickness, upper labial bending degree, and anterior nasal angle in the lateral aspect of the upper facial soft tissue tended to be smaller and upper labial height greater than those in the control group. A distinct difference between subjects and controls was observed in upper labial height in the CL(P)-F and CL(P)-M groups and in upper labial bending degree in the CP-F and CP-M groups. (5) Although no distinct difference was observed between controls and the parent groups in terms of facial angle and SNB angle, mandibular plane angle and gonial angle were relatively large and incisor axial angle was small in the parent groups.(ABSTRACT TRUNCATED AT 400 WORDS)