DNA fragments ranging in size from 0.1 to 10.0 kbp were separated by constant electric field, square-wave pulsed electric field, and inversion pulsed electric field in hydroxyethylcellulose (HEC, 1300 K) polymer. The influence of electric field modes on the separation performance of DNA fragments was investigated when the modulation depth of pulsed electric field varied. We found that when other electrophoretic conditions were the same: (1) under constant electric field, DNA fragments can only be effectively resolved up to 1.0 kbp, whereas DNA fragments above 1.0 kbp co-migrated; (2) under square-wave pulsed electric field, high modulation depth favors the resolution of larger DNA fragments higher than 1.0 kbp, simultaneously the resolution of DNA fragments between 0.6 and 1.0 kbp deteriorates with the growth of modulation depth; (3) under inversion pulsed electric field, DNA fragments ranging in size from 0.1 and 8.0 kbp can be effectively resolved with high resolution. Furthermore, we have successfully separated the λ-DNA endonuclease fragments digested by EcoT14 I/Bgl II under inversion pulsed electric field. The results above demonstrate that inversion pulsed field capillary electrophoresis is a method with fast speed, accuracy, high reproducibility, and thus it can be applied for the separation of DNA fragments with a wide molecular range.