Parent-adolescent communication about sexual and reproductive health (SRH) issues is associated with healthy sexual outcomes in adolescents. The increasing evasion of this discourse at the home front in sub-Saharan Africa is receiving greater academic and public health attention. In many Nigerian households, adolescents lack access to informative and undiluted communication with their parents, a situation that is worse for adolescents dwelling in slums. This study documented SRH issues and patterns of parent-adolescent communication in selected slums of Ibadan, Southwestern, Nigeria. A mixed sequential explanatory research was carried out in 10 selected slums in Ibadan, Oyo State, Nigeria. A structured questionnaire scripted on open data kits (ODK) and vignette for Focus Group Discussion (FGD) were used to obtain data from parents and adolescents. A sample of 796 parent-adolescent dyads was interviewed for the quantitative strand, and 8 FGDs were conducted for the qualitative component. Analytical techniques utilized for quantitative data included descriptive (frequency counts and percentages) and inferential (chi-square) statistics, while descriptive and interpretative analyses were adopted for qualitative data. Communication regarding SRH issues occurs in many households, but indirectly. A higher proportion of mothers discuss all SRH issues with their adolescents and better than fathers. While female adolescents engage their parents only on limited topics, the consequences of sexual behaviors are the least discussed. The chi-square values for each topic were not significant for parents and adolescents, however, only the discussion of preventive sexual practice was significant for parents (0.042) at a significant level of 0.05 and adolescents (0.000) at a significant level of 0.01. The findings of this study suggest that sexual education training intervention is germane to enhancing parent-adolescent communication on SRH issues for parents and adolescents.