OBJECTIVE To screen the most strong emodin derivative inhibiting the proliferation of multiple myeloma(MM) cells and to explore the inhibitory and inducing effects of emodin derivatives on proliferation and apoptosis of MM cell lines RPMI 8226 and U266. METHODS Sixteen emodin derivatives were designed and synthesized by using emodin as mother substance, then from which the emodin derivative E11 was screened for experiments. The MTT method and cell colony formation assay were used to observe the effect of E11 on proliferation of RPMI 8226 and U266, the fluorescent microscopy with DAFI staining was used to observed the morphological changes of MM cells treated with emodin dervative 11, the DNA fragmentation detection was used to detect the inducing apoptosis effect of E11 on RPMI 8226 and U266 cells treated with E11. RESULTS The MTT assay showed that after the RPMI 8226 cells were treated with 16 kinds of emodin derivatives for 48 hours, the 50% inhibition concentration（IC50） of 14 emodin dervatives was between 0.83-34.68 µmol/L, except E10 and E15 because their IC50 could not be calculated. The IC50 of E11 for RPMI 8226 and U266 cells were 0.831±0.0453 µmol/L and 1.039±0.093 µmol/L, respectively. Cell colony formation assay showed that E11 could inhibit RPMI8226 and U266 cells' colony formation in dose-.and time- dependent manner (r=0.72). Cell apoptosis was observed in RPMI8226 and U266 cells by DAPI staining , and also by the detection of DNA fragmentation. CONCLUSIONS In the synthesis of 16 kinds of emodin derivatives, the inhibitory effect of E11 on prolife-ration of RPMI8226 cell was the strongest. E11 can remarkably inhibit proliferation and induce apoptosis of RPMI8226 and U266 cells.