The authors have experienced a fracture in the ceramic head in a total hip arthroplasty in three cases. Two of these were comminuted and the other was a hair-line fissure. A foreign body, perhaps from the operation, existed between the neck of the stem and the head in two cases (one in a comminuted fracture and the other in the fissure fracture). The other case had no foreign body, and, judging from the serial radiographs, the fracture was probably caused by weight-bearing stress. Care must be taken during operation to avoid interposing any foreign body in the modular ceramic head total hip arthroplasty, and the weight-bearing stress factor must be considered as an indication for a ceramic head fracture in young active patients.