PURPOSE: To determine whether the biopsy core number and time interval between prostate biopsy and radical prostatectomy affect the operative and oncologic outcome of robot assisted laparoscopic radical prostatectomy (RALP). MATERIALS AND METHODS: From January 2008 to April 2009, a single surgeon performed 72 RALPs after an initial learning period of 30 cases. The relationship between time from biopsy to prostatectomy and biopsy core number with operative time and estimated blood loss (EBL) were initially evaluated with a linear regression model. These patients were classified into groups according to whether the interval from biopsy to RALP was within four weeks or not, and whether there were less than or greater than 10 core specimens removed. RESULTS: RALP was performed in 34 patients within four weeks of biopsy, and in 38 patients more than 4 weeks after biopsy. According to the number of core specimens removed, less than 10 cores were performed in 10 patients, and more than 10 cores were performed in 62 patients. Using an interval of 4 weeks as the cutoff point, early surgery was associated with longer operating time (232.6 vs 208.8 min) and increased estimated blood loss (305.1 vs 276.9 mL). For cases with more than 10 biopsy cores, there was a slight increase in operative time (229.2 vs 210.3 min). None of these differences were statistically significant by multivariate analysis. CONCLUSION: Our data suggests that there is no reason to delay RALP to more than 4 weeks after prostate biopsy. It also revealed that the number of biopsy cores (up to 14) did not influence operative outcome. Thus, RALP is a feasible procedure regardless of the biopsy related prostate state.