Decision-making on marriage of sons and daughters represents one of the most culturally significant and sensitive household decisions in India. Involvement of older family members in such matters reflects their status, authority, and perceived wisdom, and serves as an important indicator of intergenerational unity. However, empirical evidence on the extent and determinants of older adults’ participation in marriage-related decisions remains scarce. This study examines the role of older adults (aged 45-59) and the elderly (aged 60 and above) in decision-making about their children’s marriage, and assesses how socio-demographic and economic factors shape this involvement. The analysis uses data from Wave 1, after excluding respondents younger than 45 years, the final analytical sample includes 66, 606 individuals 34, 704 older adults and 31, 902 elderly. Participation in marriage decisions measured based on LASI's three-category decision-making item, later recoded into a binary outcome distinguishing “any role” (decides alone or jointly) from “no role.” Descriptive findings show that 95% of individuals aged 45 and above report having some role in their children’s marriage decisions, though substantial differences exist between age groups. While 97% of older adults (45-59) play a role, the proportion declines to 92% among the elderly (60+), indicating reduced involvement with increasing age. Men, the more educated, the currently working, and those in higher MPCE quintiles show greater involvement. Logistic regression analyses further confirm these associations: female respondents and those with lower education or economic status have significantly lower odds of participating, whereas socioeconomically advantaged groups and the more educated are more likely to be involved. Differences between rural and urban areas also emerge, with contrasting patterns across the two age groups. Overall, the study highlights meaningful disparities in decision-making authority among older Indians, shaped by age, gender, socioeconomic position, and household context. These findings emphasize the need for greater attention to intergenerational inclusion, as declining involvement of the elderly reflect broader vulnerabilities related to ageing, marginalization, and changing family structures.