The present study was carried out to evaluate some cardiovascular effect of Rosiglitazone, Nigella sativa, silymarin each alone and the combination of Rosiglitazone with either Nigella sativa or Silymarin in order to get the best combination to avoid the possible side effects produced by Rosiglitazone. This was done through studying the effect of the test plant drugs and their combination on some hematological parameters and hormone control on heart activity (Lactic dehydrogenase enzyme) (L.D.H) .seven groups of adult male rats each of 10 (200-250 gm / b. wt) were used in this study. Hyperglycemia was induced in six groups of rats. Whereas, the 7t group was left as normal control group. All treatments were given orally daily for successive 28 days .The 1^st group was left without treatment and kept as STZ diabetic. The 2^nd group was administered Rosiglitazone (0.58mg/100gm.b.wt) , The 3^rd group was given Nigella sativa (0.25gm/100gm.b.wt) , the 4^th group was given Silymarin (50mg/100gm.b.wt), the 5^th and 6^th groups were administered the combination of Rosiglitazone with either Nigella sativa or Silymarin respectively in the same recommended doses. Blood samples were collected after the 1st, 2nd, 3rd and 4th week post drug administration. Serum was separated and used for determination of various variables. The results showed that Rosiglitazone afforded a marked non significant changes in RBCS. WBCS with significant decrease in hemoglobin percent in Rosiglitazone treated group with marked increase in LDH hormone which reflect the activity of the heart when compared with diabetic non treated group and diabetic group treated with Rosiglitazone drug + Silymarin and Rosiglitazone drug + Nigella sativa.