The identification of clinically-relevant early diagnostic and prognostic protein biomarkers is essential to maximize therapeutic efficacy and prevent cancer progression. The aim of the current study is to determine whether aberrant plasma protein profile can be applied as a surrogate tool for early diagnosis of bladder carcinoma. Plasma samples from patients with low grade non-muscle invasive bladder cancer and healthy controls were analyzed using combined 2D-DIGE and mass-spectrometry to identify differentially expressed proteins. Validation was performed using western blotting analysis in an independent cohort of cancer patients and controls. Fifteen differentially-expressed proteins were identified of which 12 were significantly up-regulated and three were significantly down-regulated in tumors compared to controls. The Ingenuity Pathways Analysis revealed functional connection between the differentially-expressed proteins and immunological disease, inflammatory disease and cancer mediated through chemokine and cytokine signaling pathway and NF-kB transcription factor. Among the three validated proteins, haptoglobin was able to distinguish between patients with low grade bladder cancer and the controls with high sensitivity and specificity (AUC > 0.87). In conclusion, several biomarker proteins were identified in bladder cancer. Haptoglobin is a potential candidate that merit further investigation to validate its usefulness and functional significance as potential biomarkers for early detection of bladder cancer. Bladder carcinoma (BC) is the second most common cancer of the genitourinary tract and a leading cause of mortality worldwide. According to a recent data, an estimated 450,000 persons developed BC and more than 199,000 persons died of BC in the year 2018 1. Early diagnosis of bladder cancer has a better prognosis with a 10-year disease-free survival of 86% for non-muscle invasive bladder cancer (NMIBC) (stage T0). However, due to the absence of reliable prognostic markers, recurrence rates fluctuate between 30 and 70% with as high as 10-30% rates of progression to muscle-invasive bladder cancer (MIBC) phenotype for high-risk patients 2,3. This situation necessitates vigilant management protocol through frequent cystoscopy/cytology examinations and different treatment modalities. The extended treatment and long-term follow-up make bladder cancer treatment one of the most expensive per patient among all cancers 4. Therefore, biomarkers for early stage screening of non-muscle invasive bladder cancer is desperately needed as it will help in early diagnosis, preventing disease progression to a life-threatening phenotype (MIBC) and will eventually lower the associated costs of treatment. Furthermore, early diagnosis of bladder cancer would be of great importance in discerning patients with high grade cancer from those with low grade cancer and in selecting the appropriate therapeutic approaches. Despite development and FDA-approval of several urine and blood-based biomarker kits for appraisal of bladder ca...