President Kovind's remarks came at the end of a month-long march across the country to raise awareness about the slavery, trafficking, and sexual abuse of children.
Prime Minister Narendra Modi's vision of a "New India" - which promises housing, electricity, healthcare and education for all - cannot be realised unless the issue of sexual violence against children is addressed, the country's president has said.
President Ram Nath Kovind made the remarks at an event marking the end of a month-long march across India by campaigners led by Nobel laureate Kailash Satyarthi to raise public awareness about the trafficking, slavery and sexual abuse of children.
"The Prime Minister talks about a 'New India' referring to improved infrastructure in the country. The concept is good," said Kovind, referring to Modi's pledge in August to make a better country for all by its 75th Independence Day in 2022.
"But even if all that is achieved, if the issue of child sexual abuse - and the other sensitive crimes against children - are not addressed, I think that we miss making this concept possible when we celebrate 75 years of freedom."
Children in India face threats ranging from trafficking, sexual violence, forced labour and early marriage to a lack of access to quality education and healthcare, say activists.
More than 9000 children were reported to have been trafficked in 2016, a 27% rise from the previous year, according to government data.
Most are from poor rural families who are lured to cities by traffickers who promise good jobs but then sell them into slavery as domestic workers, to work in small manufacturing units, farming or pushed into sexual slavery in brothels.
Figures from the National Crime Records Bureau also show that almost 15,000 children were victims of sexual violence such as rape, molestation and exploitation for pornography in 2015 - up 67% from the previous year.
But the figures are underestimates in socially conservative India, say activists, where fear of being blamed and shamed means victims often keep quiet and do not report abuses.
Child rights activist Satyarthi, whose charity Bachpan Bachao Andolan (Save the Childhood Movement) has rescued over 80,000 enslaved children, launched his India-wide march or "Bharat Yatra" from the nation's southern-most tip on September 11.
Over the last five weeks, participants travelled over 7000 miles across 22 of India's 29 states. They held events in towns and villages, engaging politicians, judges, students, religious leaders and community members.
Over 60 million people across India took part - either by attending events such as plays and concerts or by voicing their support on social media over the last 35 days, say organisers.
The "Bharat Yatra" also mobilised government officials and policymakers as well as Bollywood stars, they added.
Home Minister Rajnath Singh has promised to pass an anti-trafficking bill which has been pending for over a year, chief ministers pledged to take steps to curb child abuse and the judiciary promised to set up children's courts.
The campaign also saw Bollywood stars and singers such as Amitabh Bachchan, Anupam Kher, Dhanush, Latha Rajinikanth and Vivek Oberoi support the campaign and take a pledge to help end the buying, selling and sexual exploitation of minors.