Electron cooling devices for HIRFL-CSR were under construction through collaboration between BINP and IMP [1]. The main parameters, design points and progress of the cooler devices will be presented. The electron motions in the gun region, adiabatic expansion region, toroid region and collector region were simulated with the help of numerical calculation. Cooling times of the typical heavy ions with injection energy were calculated with aid of the code. The prototypes of solenoid coils at the cooling section were fabricated and measured, the results show that the transverse components of the magnetic field for single coil is less than 2×10 -4 .