Background: Cervical cancer is the first female cancer in Lao PDR, a low-income country with no national screening and prevention programs for this human papillomavirus (HPV) associated pathology. HIV-infected women have a higher risk of persistent oncogenic HPV infection. The purpose of this study was to determine the knowledge, awareness and attitudes about cervical cancer among Lao women attending or not an HIV treatment center, in order to understand if this attendance had offered an opportunity for information and prevention. Methods: A cross-sectional case-control survey was conducted in three provinces of Lao PDR, Vientiane, Luang Prabang and Savannakhet. Cases were 320 women aged 25 to 65, living with HIV and followed in an HIV treatment center. Controls were 320 women matched for age and place of residence, not attending an HIV treatment center. Results: Cases had a greater number of sexual partners and used condoms more often than controls. Only 36.6% of women had consulted a gynecologist (47.5% among cases and 25.6% among controls, p < 0.001) and 3.9% had benefited from at least one Pap smear screening (5.6% cases and 2.2% controls, p = 0.02). The average knowledge score was 3.5 on a 0 to 13 scale, significantly higher in cases than in controls (p < 0.0001). Despite having a lower education level and economic status, the women living with HIV had a better knowledge about cervical cancer and were more aware than the controls of the risk of developing such a cancer (35.9% vs. 8.4%, p = 0.0001). The main source of information was healthcare professionals. The main reasons for not undergoing Pap smear were the absence of symptoms and the default of medical injunction for cases, the lack of information and ignorance of screening usefulness for controls. Conclusion: In Lao PDR, routine consultation in HIV treatment centers is not enough harnessed to inform women of their high risk of developing cervical cancer, and to perform screening testing and treatment of precancerous lesions. Implementing this cost-effective strategy could be the first step toward a national prevention program for cervical cancer.