The experiment was carried out at two locations, the first in Ramadi - Kaldia (80 km) west of Baghdad, the second at the farm of College of Agriculture, University of Baghdad, during the spring season 2017, in order to study the effect of concentrations and application growth stage of ethephon on growth, yield, and its components of sorghum (cv. Buhooth 70). Split plot arrangement was used according to RCBD. The application growth stage 4, 6 and 8 leaf growth stage, occupied the main plots while Ethephon concentrations 0, 500, 1000 and 1500 mg L-1, occupied the sub-plots. Results showed at both seasons, that the high concentration (1500 mg .L-1) gave the lowest plant height, leaf area, number of leaves and grain yield, thus reducing the biological yield 2.302 and 2.515 ton ha-1, for both locations respectively, While the concentrations 1000 and 500 mg.L-1, gave the highest grain yield 3.976 and 3.741 ton ha-1, for both locations respectively, the application times according to growth stages also had a significant effect on number of days to flowering stage and maturation also weight of 500 grains and grain yield. Application at 4 and 6 leaf growth stages gave highest grain yield in both locations 3.464, 3.673 ton ha-1 respectively, also the most traits under study were significantly influenced by the interaction between concentrations and application time, the highest yield 5.127 ton ha-1 in Ramadi location, was obtained from interaction treatment (1000 mg L-1 * 8 leaf growth stage) was while in Baghdad location the interaction treatment (500 mg L-1 * 6 leaf growth stage) gave the highest yield 4.623 ton ha-1.