This research was conceptualized in the context of the increasing prevalence of sexually transmitted infections (STIs) among Filipino youth. Formulating effective sexual health programs and policies necessitate research on target populations. However, the participation of young in research in health research requires parental consent. This explanatory mixed method study attempted to understand the consenting and non-consenting behaviors of parents to allow their minor-aged children to participate in these research endeavors. The study recruited thirty-five (n=35) parents from Metro Manila and Laguna through convenience sampling. Using a quantitative survey questionnaire, the respondents were asked to rank fourteen hypothetical research topics on sexual and reproductive health in terms of their likelihood of allowing their child to participate in the study. They were then interviewed to explain their considerations for their ethical decisions. The top three topics that parents would likely to give consent to are (1) children‘s understanding of the roles of males and females in society, (2) knowledge, attitudes and practices on family planning and birth control and (3) knowledge on and practices related to HIV and other sexually transmitted infections. The top three that the parents would likely to refuse to give consent are (1) exploring the child participants‘ current sexual activity with partners, (2) knowledge, attitudes and practices of masturbation and self-pleasure, and; (3) exploring child participants‘ non-conventional sexual preferences. Qualitative findings reveal norm and attitude related factors for these ethical decisions.