The invention discloses a spring operation mechanism for a modularized vacuum circuit breaker. The spring operation mechanism is characterized by comprising a right mechanism plate (1) and a left mechanism plate (15) which are oppositely arranged, wherein an energy-storing motor (2) is arranged on the right mechanism plate (1); an output shaft (28) of the energy-storing motor (2) is penetrated through the right mechanism plate (1); a pinion (4) is sleeved on the output shaft (28); the pinion (4) is meshed with a gear (5); a shaft (30) is connected with the gear (5) and a middle pinion (29); the middle pinion (29) is meshed with an energy-storing gear (10); and the energy-storing gear (10) and a cam (25) are connected to an energy-storing shaft (12). The spring operation mechanism for the modularized vacuum circuit breaker, provided by the invention, has the advantages of multifunctional parts, greatly reduced total amount of parts, simple structure, small volume, light weight, low cost, long service life and easiness in maintenance and repair.