Objective: This study was performed to assess prostate biomarkers with reference to body mass index and duration of prostate cancer. Materials and Methods: A hospital based retrospective study was undertaken using data retrieved from the register maintained in the Department of Biochemistry of Manipal Teaching Hospital, Pokhara, Nepal between $1^{st}$ January, 2009 and $28^{th}$ February, 2012. Biomarkers studied were prostate specific antigen (PSA), acid phosphatase (ACP) and prostatic acid phosphatase (PAP), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (${gamma}GT$). Demographic data including age, duration of disease, body weight, height and body mass index (BMI) were also collected. Duration of disease was categorized into three groups: <1 year, 1-2years and >2 years. Similarly, BMI ($kg/m^2$) was categorized into three groups: <23 $kg/m^2$, 23-25 $kg/m^2$ and >25 $kg/m^2$. Descriptive statistics and testing of hypothesis were used for the analysis using EPI INFO and SPSS 16 software. Results: Out of 57 prostate cancers, serum level of PSA, ACP and PAP were increased above the cut-off point in 50 (87.5%), 30 (52.63%) and 40 (70.18%) respectively. Serum levels of PSA, ACP and PAP significantly declined with the duration of disease after diagnosis. We observed significant and inverse relation between PSA and BMI. Similar non-signficiant tendencies were apparent for ACP and PAP. Conclusions: Decreasing levels of prostate biomarkers were found with the duration of prostate cancer and with increased BMI. Out of prostate biomarkers, PSA was found to be significantly decreased with the duration of disease and BMI.