Height adjusting structure for desk

A height adjusting structure for a desk with two supports being applied to adjust a height of a desktop which is connected at two opposed bottom side ends thereof with two first supporting tubes fitted with two second supporting tubes and comprising:

• a through hole defined adjacent to a top end of each second supporting tube to expose each first supporting tube fitted in each second supporting tube;
• two adjustors arranged adjacent to two top ends of the two second supporting tubes, wherein one of the two adjustors has a swing lever disposed thereon to drive a driving gear and has a driven gear driven by the driving gear, and the other of the two adjustors has a driven gear fixed therein and simultaneously rotating with the driven gear of one of the two adjustors through a connecting rod, such that two driven gears of the two adjustors engage with two toothed sections of the two first supporting tubes, and after the swing lever is rotated clockwise or counterclockwise, the driving gear is driven by the swing lever to rotate clockwise or counterclockwise, then the two driven gears are driven to rotate simultaneously through the connecting rod and to movably engage with the two toothed sections of the two first supporting tubes, thus moving the two first supporting tubes upwardly and downwardly to adjust a height of the desktop.