When a filament in an active region quickly ascends, the underlying current sheets reconnect with one another and produce strong electric fields, which may accelerate electrons. On the basis of this physical process and by means of solving the Fokker-Planck equation, which includes Coulomb collisions and ion-acoustic turbulent scattering, the evolutionary characteristics of electron distribution function have been obtained. The results of calculations show that (1) When the intensity of electric field is 1-10V cm - 1 , then in 10 - 5 -10 - 6 s electrons may be accelerated to the order of 0.1-1 MeV; (2) The accelerated electrons approximately exhibit power-law distribution and its spectral index basically coincides with that inferred from the microwaves and hard X-rays of flares during the impulsive phase.