Background: Transitional cell carcinoma (TCC) of the bladder is the second most common malignancy of the genitourinary tract and the third most common cause of death among people with genitourinary tumors, besides, tumors of the bladder are an important source of both morbidity and mortality. Objectives: The purpose of the study are 1. formulate an idea about the number of patients with bladder cancer (TCCs) in sample of Iraqi population. 2. Study the histopathological features of TCCs of bladder 3. Assessment the prevalence of (TCC) of bladder in both sex (male and female) with smoking as risk factor. Patients and Methods: A study was conducted at one institution were identified that teaching-hospital of Baghdad. All patients included in the present study diagnostic with TCC of bladder. The total of subjects participated in the study were 42 patients and 20 subjects as control through six months’ period from July 2014 to January 2015. Results: The mean of participates age was 655.7 years and the youngest was 21years and the oldest was 75 years. Out of 42 patients, the most common age group was 54-64years (52.38%) with Male to female ratio was 5.2:1.32 were male 32 and 10 were females. However, the prevalence bladder cancer (TCCs) was higher in male than in female, with more pronounced decreases in younger age (≤31year) 3(7.14), have been found. In addition, age specific rate was observed higher in the older age groups for most patients with cancer. The population attributable risk for ever smoking in our study was 33(78.57) out of 42 patients. Moreover, current study shows there was a correlation between grade and stage of bladder TCC, 24(57.14%) bladder TCCs that classified as grade I, while 2(4.76%) of bladder TCC were classified as grade II. Conversely, of the bladder TCC lesions (11.9%, 14.28%, 57.14 and 4.76) were stage (pTa-T1-T2-T3) respectively. Although this study showed 5(11.9) little-known stage and grade. The area of histopathological changes included were showed hyperplastic changes, involving the entire bladder lining, that ranged from flat hyperplasia to small areas of nodular and papillary hyperplasia. The smallest recognizable nodular and papillary lesions were associated with angiogenesis in the contiguous stroma. In addition, there were chromatin irregularities and nucleoli of variable numbers, shape and size. Nuclear chromatin irregularity and mitoses were easily identified, these cells continued to have the appearance of hyperplastic epithelium. The changes noted by generalized and orderly proliferative reaction and appeared reparative. Conclusions: Our study has revealed that the bladder TCC, where appeared the high prevalence and incidence rate of TCC of bladder in sample of Iraqi population were of concern, especially for older age groups.