The aim ofthis study was transforming doxorubin by encapsulating it in mesoporous silica compared to free doxorubicin. In vivo study, free doxorubicin, mesoporous silica preparations were assessed by different measurements like particles size, zeta potential and TEM. Several parameters have been measured to assess the cardiotoxicity (Albumin, lactate dehydrogenase (LDH), Aspartate Aminotransferase (AST), Anticardiolipin IgG, Creatine kinase-MB (CK MB), C-reactive protein (CRP), Tumor necrosis factor (TNF α)).The experimental animals were divided into seven groups as follow: group (1) Control. (2) Group B:received doxorubicin. (3) Group C: mesoporousdoxorubicn. Rats injected withfree doxorubicin caused significantly elevated levels of all parameters measured compared to control group (albumin 4.435 ±0.085 vs 2.910 ±0.10, anticardiolipin 9.4 ± 0.256 vs 19.31 ±0.4391, AST 64.60 ± 1.79 vs 244.8 ± 9.86,  CK 14.04± 1.794 vs 73.25± 1.240, CRP 4.904±0.45 vs 23.96 ± 0.95, LDH 212±10.1 vs 754±16.4, TNF α 34.62±1.05 vs 126.6±6.25). In addition there was a significant variation of mesoporous silica results compared to free doxorubicin. Conclusion: There was a marked cardiotoxicity of doxorubicin could be decreased by transforming it into mesoporous form.