KNOX genes encode the homeodomain transcription factors that play an important role in maintaining the activity of shoot apical meristem in plants as well as in morphogenesis and secondary growth in many green plant species. In this work, the authors used the in silico methods to identify and analyze the KNOX genes in the whole genome of Clementine (Citrus clementina) that has high values. Totally, 10 KNOX genes were genome-wide identified in the Clementine. All often KNOX genes contain two conserved domains, KNOXI (PF03790) and KNOX2 (PF0379 I). However, two other conserved domains, ELK (PF03789) and Homeodomain (Homeobox_KN, PF05920), only present in nine out often. The clementine KNOX genes are discontinuous coding genes which include from two to five introns depending on the gene. Each gene encodes a protein that has from 124 to 450 amino acids in length. In addition, the KNOX proteins are apparently acidic, their pI are in the range of 4,44 - 6,16. These CclKNOX genes are distributed on 5 out of 9 chromosomes. Two genes, CclKNOXl-l and CclKNOXl-2, were formed in a chromosomal segment duplication event. The CclKNOX genes are classified into three sub-groups, KNOX I, KNOX II and KNOXM that has 6, 3 and I genes, respectively. The result of promoter in silico analysis suggested that the CclKNOX genes were weakly regulated by abiotic stresses of environment but strongly regulated by phytohormones, auxin, gibberellins and brassinosteroides, in particular. Six out of 10 CclKNOX genes express in the tissues containing the shoot apical meristem, among which the subgroup II KNOX genes express strongest.