Abstract: Objective To compare the effects of chloroform, xylene, d-limonene on cleaning root canals in root canal retreatment. Methods 60 mandibular first premolars were randomly divided into three groups, with 20 teeth in each group . A week after root canal filling，different solvents were used to help clean root canals. The treatment time and the volume of the solvents used were compared. Results Chloroform group consumed the least time to get the original working-length. But its overall clinical operation time and amount of solvent used was not significantly different with those of xylene group(P<0.05). All kinds of clinical operation time were significantly longer in d-limonene group(P<0.05), and more solvent was used(P<0.05). Conclusions In clinical operations, xylene can be used instead of chloroform for fast root canal cleaning. If there is no strict requirement on operating time, d-limonene may be a better choice.