This thesis aims to examine the effects of the systemic immune response triggered by the transurethral enucleation and resection of the prostate (TRERP). 60 patients with benign prostatic hyperplasia (BPH) were randomly classified into enucleation group and resection group. The level of WBC, serum IL-6, IL-8, CRP, IgG, IgA, IgM, CD4+, CD8+,and ratio of CD4+ to CD8+ (BPH)were compared and analyzed preoperatively and on the 1st, 3rd, 5th of postoperative day. The result demonstrates the statistical significance of the differences between the two groups on the amount of resected tissues, postoperative blood loss, and operation time. To the contrary, there was no statistical significance of the differences on WBC, IL-6, IL-8 and CRP level. To elaborate, on the 1st postoperative day, the values of WBC, IL-6, IL-8 and CRP level were significantly higher, whereas the values of IgG, IgA, IgM, CD4+, CD8+ level and ratio of CD4+ to CD8+ of both groups were significantly lower. On the 3rd postoperative day, there was statistical significance of the differences between two groups on WBC, IL-6, IL-8, CRP level. On the 5th post operative day, however, no statistical significance of differences existed on the IgG, IgA, IgM, CD4+, CD8+ level and ratio of CD4+ to CD8+. It is concluded that compared to the transurethral resection of the prostate (TURP) for Benign prostatic hyperplasia (BPH), TRERP has prominent advantages of more radical resection, less blood loss and less immune suppression.