"This is a great drama of our times, you know to live without God," said Marc Cardinal Ouellet in an interview with CBC Television.
"They need the Creator, they need this relationship. It is vital, you know, for family life, for social life, for fraternity, for peace."
Ouellet says the church has to respond to the needs of people who aren't religious.
When asked whether he believed the church needed to forge ahead on social issues such as its positions on gay marriage and abortion, the 68-year-old Quebecer was evasive, saying questions on those areas were "secondary."
Ouellet did share his views on the role of women in the church, however, saying "there is much more to do."
While he would not support the ordaining of women, Ouellet said many women were already working in key positions in the church.
"This is open to further development, but we have to go you know with the time. And it is not easy to move forward," he said in what was the second instalment of a two-part interview.
Ouellet leads the powerful Congregation for Bishops in the Vatican, which vets bishop nominations worldwide, and has worked in Latin America and in Rome.
The former Archbishop of Quebec City is often regarded as a conservative figure and has drawn criticism in the past with his opinions on social issues.
He came under fire in Quebec for anti-abortion remarks he made in 2010 when he said abortion was unjustifiable, even in cases of rape. His words drew angry reactions from women's rights activists and a number of politicians.
He has also spoken out against gay marriage, calling it "a big crisis."
Ouellet is considered one of the front-runners to replace the retired Pope Benedict, who stepped down last week citing a lack of strength to do the job.
Pre-conclave meetings are currently underway at the Vatican. An official date has yet to be set for the conclave during which a new pope will be elected.