Presented in this paper the data from a chromosome study of 397 patients referred for suspected chromosmal abnormalities. Karyotypes were obtained using short-term blood culture and direct method. Of these 238 patients had normal chromosome complements; 159 (40.1%) patients had chromosome abnormality. Among all patients with chromosome abnormalities, 82.4% (131/159) had aberrations of chromosome number, the others 17.60/0 (28/159 had aberrations of chromosome structure. Ten had a chromosome rearrangement; Five of them were reciprocal and five Robertsonian translocations. Four patients with pericentric inversions and one with paracentric inversions and four with isochromosomes were observed. There were four patients with marker chromosome, two patients had a chromosome insertion; and three others. (additional abnormal chromosomes.) Thus the results of the present study indicate the importance of cytogenetic evaluation in clinically abnormal patients.