This study utilized data from Bangladesh Demographic and Health Survey 2004 to identify the determinants of knowledge about AIDS for women of urban and rural area of Bangladesh, Bi-variate and multivariate logistic regression methods were employed in analyzing data. This study found that a wider gap exists between urban and rural areas regarding knowledge about AIDS, where every 8 out of 10 urban women know about AIDS but almost half of the rural women still do not know about AIDS. Mass media play a major role for growing awareness about AIDS in both of these areas. In the urban area 61.6 percent women knew at least one correct way to avoid AIDS but rural women are in miserable condition because the corresponding figure for rural women was only 31.3 percent that means 37.7 percent and 67.7 percent among urban and rural women respectively still did not know how to avoid AID. Binary logistic regression method shows that that education, occupation, ever use of contraception, currently using condom, permission to go to hospital/health center, mass media exposure, region of residence and wealth index significantly influence the knowledge about AIDS among rural women, whereas, in the urban areas except occupation and currently using condom all these remaining variables appear as the significant predictors of knowledge about AIDS.