Sandberg shot to global fame after her the publication of her best-selling book Lean In: Women, Work and the Will to Lead which talks about women's career struggles and advises women to "lean in" to reach their potential.
It has drawn bouquets from admirers for articulating a new modern feminist vision and brickbats from critics who say her lofty position has made her out-of-touch with the gruelling personal cost of combining career and family.
In an interview with India's Mint business daily, the 43-year-old admitted: "I cry at work," adding women are not "one type of person Monday through Friday" and "then a different person in the nights and weekend."
"I think we are all of us emotional beings and it's okay for us to share that emotion at work," said Facebook's number two, who was named in Time magazine's 2013 list as one of the 100 most influential people in the world.
Studies have shown women are more prone than men to cry at work because males are schooled not to cry in public and it can hurt their career progression.
Sandberg, who is married with two young children, said on the subject of her book "the messages of believing in yourself and sitting at the table, getting compensated fairly, those can happen at any point in your career."
It is necessary to talk about gender-related issues honestly in the workplace, and a need for employers to say: "I am here to support you", she added in the interview.
The question of whether women can "have it all" in terms of pursuing careers and raising families is "very problematic", added Sandberg, who got $26.2 million in salary, bonus and shares last year from the US social networking giant.
Men never face such questions because society assumes they can have both professions and children, she said in the interview.
A huge percentage of women globally have both children and work full-time, but to do so they must get the "support they need at the workplace and at home," Sandberg said. – AFP