The utility model discloses an on - -spot ground developments compression modulus tester, including laser displacement meter (200) of standing on foundation surface, stand on the experiment load mechanism on the ground to and data processing case (100), be provided with on experiment load mechanism stabilizing support (4) vertical slide rail (20). The loading hammer (8) of counter -force module (5), linear vibration exciter (6), small size connects firmly as an organic wholely to through the hookup of assembly pulley (3) slidable ground on stabilizing support (4), slide rail on assembly pulley (3) and the stabilizing support agrees with, linear vibration exciter (6) are two synchronous machine, and motor output shaft is provided with eccentric block group (9), loading hammer (8) overhead has force transducer (7) that acquire the loading impact force. The utility model provides a device, the structure is reliable, and is easy and simple to handle, each module removable assecmbly, the tester is reconnoitred to the very big vast line that has made things convenient for.