Providing the HPV vaccine at no cost in Bangladesh portrays a significant innovation in public health. Although the HPV vaccine has been implemented for adolescent girls in most schools from rural to urban regions, subsequent uptake among adolescents has shown an observable decline. This study addresses a significant gap by examining how adolescent women’s knowledge and social beliefs shape their engagement with the HPV vaccine. Based on the Diffusion of Innovation Theory, the research critically analyzes perceptions of vaccines and behavioral orientations shaped by socio-cultural beliefs. A phenomenological qualitative design was employed, using purposive sampling to recruit 20 participants. Data were collected through in-depth interviews and thematically analyzed to identify recurring patterns related to social beliefs about this vaccine. Diffusion of innovation theory suggests that the effective implementation of an innovation within a society depends on its five core dimensions – relative advantage, compatibility, complexity, trialability, and observability. The findings of this research reveal that the HPV vaccination program remains limited in aligning with these dimensions. Findings reveal that a lack of knowledge, incompatibility, limited awareness, and culturally insensitive communication play a critical role in shaping misconceptions about vaccine implementation in healthcare, as well as undermining trust and sustained participation. The perception of HPV vaccination as an unnecessary, sensitive intervention shaped by socio-cultural beliefs undermines motivation to engage in vaccination uptake.