The digital-first campaign will see a week of content across thesun.co.uk under the You're Not Alone umbrella, which began on Monday to coincide with World Suicide Prevention Day.
Suicide remains the biggest killer of people under the age of 35, and men are three times more likely to take their own life than women, say the publishers.
Monday's newspaper featured a hard-hitting interview with former Atomic Kitten star Kerry Katona, who tells all about her own struggles with mental health and thoughts of suicide. Online, the campaign has launched alongside video produced by The Sun's in-house team as well as social content.
Other content includes an investigation into a sick 'suicide video' trend on YouTube and advice on the top ten warning signs that friends or family might be struggling. Articles will also feature on Fabulous, The Sun's female lifestyle brand, over the week as the publishers look to land this campaign across as many channels as possible.
The rest of the week will see stories of brave survivors, relatives left behind, "good samaritans" and share tips from mental health experts across all sections of The SunOnline.
Laura Whitcombe, Digital Campaigns Editor at The Sun, said: "The Sun is committed to getting people talking about this important issue. For too long, stigma surrounding mental health has prevented people from accessing life-saving and life-changing support. We hope the stories we will tell across the campaign this week will help to change that."
Backing the campaign, Ruth Sutherland, CEO of The Samaritans, said: "We need to get the message across to everyone that anyone can be affected by suicide, but everyone can help. There will be times in all our lives when we need help, and as many as one in five of us have suicidal thoughts. It's what we do about that which is important."
Keith Poole, Editor of The Sun Online, said: "This is a vital campaign and we've committed to pushing it right across what is now Britain's best-read newspaper website. On this day of all days we're delighted to support the raft of charities who are doing such great work to help the most vulnerable in society."
Monday’s The Sun editorial column read: "Today marks World Suicide Prevention Day, and we're proud to support it by launching our You're Not Alone campaign. Be it veterans suffering from PTSD to simply those having a hard time, too many people still suffer in silence - with potentially devastating results. Today in print and online for the rest of the week, we will attempt to start this vital national conversation."