10 maize landraces selected from the collection of China National Genebank were planted according to the randomized block design to reveal the phenotypic diversity of quality and agronomy traits. The results showed : 1) The average oil content was 4.92%, and 11, 2 and 3 landraces were identified to reach the high oil level of class 3, 2 and 1 respectively. There was no significant difference among districts for oil content. 2) The average protein content was 12.55%, and 96% of landraces reached the protein content of class 1 of edible maize. There existed significant difference among districts for protein content. 3) The average starch content was 70.88%. No landraces reached the certificated standard of high starch maize variety. 4) Plant height, ear height and tassel branch appeared to be widely variant and significantly different among districts. The landraces from the south, southwest and northwest of China possessed stronger and higher plants and well developed tassels whereas the those from northern and northeastern China possessed relatively shorter and slimmer plants and fewer-branched tassels. 5) Among three ear traits, the highest variation belonged to ear length followed by ear row number and ear diameter. There existed significant difference among districts for these three traits. 9 landraces were identified according these 3 ear traits, of which, 5 presented the longest ear, 1 the widest diameter and 3 the largest row number. 6) There existed significant difference among districts and traits for diversity indices. Landraces from the south, east and southwest of China possessed relatively higher diversity level. Results from the phenotypic diversity analysis suggested that the evaluated landraces appeared higher oil and protein content but lower starch content. Meanwhile, landraces from southern, eastern, and southwestern China showed relatively higher diversity level than those from the other regions of the country.