Capture - recapture showed some advantages in estimation of female sex workers (FSW) in Can Tho city with estimated numbers from 2 way capture recapture of 1,768 (95 percent confidence interval: 1,5451,992) were similar with 3 way capture - recapture (1,922
1,694-2,149 respectively). Multiplier method much underestimated number of FSW with calculated result of 737. Police census was examined not appropriate for estimation of FSW in Can Tho while the figures pointed out 533 on average and 809 for high estimate. These two methods required better quality of data and collection methodology. Recommended range for FSW in Can Tho city was 1,550 to 2,000. Capture - recapture was appropriate method for estimation of FSW in a city such as Can Tho.