Most of the maize cultivars grown in the State of São Paulo and the cultivars imported from other tropical regions although vigorous have highly inserted ears. This fact makes the manual and mechanical harvesting operations difficult. In order to get preliminary information about the inheritance of this characteristic, two series of data were collected in Campinas, related to the number of internodes from the bottom of the plant to the main ear insertion and the ear height. A coeficient of variation of 4.4 per cent was obtained for the number of internodes in seven inbred lines of flint and dent corn. The coefficients for 8 single crosses and 8 double cross hybrids of the lines were 3.4 and 5.9 per cent, respectively. For the ear height in the same lines and crosses the coefficients of variation were 13.3; 9.0 and 16.0 per cent, respectively. The comparison of the internode number and its lenght indicates that the former is less influenced by the environment than the latter and can be advantageously taken into consideration in the selection for plants with low ear height. It is also suggested, based on the lines and hybrids analysed, that the internode number is controlled by factors without dominance while the ear height is conditioned by factors having heterotic effect.