Abstract: In view of the problem of short service life of electric submersible pumps in No. 2 Oil Production Plant of Tahe Oilfield, through analysis of electric pumps in shut-in wells by dismantling the pumps, and in conjunction with physical properties of heavy oil, measured temperature field data and technical parameters of previous electric pump systems, it was found that there are six factors causing short service life of electric submersible pumps for heavy oil inadequate heat-resistance of electric pump system; poor suitability of protector for heavy oil; defects of centrifugal pump shafting system and inadequate strength; improper model and design; poor heat radiation of the electric pump system; and poor effectiveness of mixing of thin and thick oils. The electric submersible pump for heavy oil was optimized and improved in terms of improvement of the technology of electric submersible pump for heavy oil, improvement of electric cable, optimization of auxiliaries of electric pump and optimization of matching technology of electric pump lifting. The well shut-in rate due to electric submersible pump and the number of wells shut in due to pump failure reduced greatly; the service life of the pumps increased evidently, providing a guarantee for normal production of the oilfield.