He was speaking at a NDTV-Aircel telethon here, organised for the second time after their 'Save Our Tigers' campaign was launched in 2010 to help raise crucial funds to protect the endangered animal.
An official report in 2011 showed India had about 1, 700 tigers, a slight improvement from the previous figures of about 1, 400 released by the government in 2008.
Poaching, shrinkage of habitat and man-animal conflict are some of the factors that threaten this animal in the wild today.
The 12-hour telethon, which began at 9 a.m., was aimed at helping raise money needed to address these issues.
Currently, India has 41 tiger reserves across 13 states.
The actor, who arrived here Saturday, was expected to take part in the entire 12-hour duration of the telethon.
Urging people involved in the illegal trade of tiger body parts, Bachchan said: "I urge you all to join this effort to save our national animal. Destroying them is like attacking and destroying our own heritage."
Eminent conservationists such as Belinda Wright, Valmik Thapar and Bittu Sahgal, among others, are participating in the event.
Wright said: "This event will inform a huge audience on the current situation of tiger conservation. I look forward to the time when a campaign like this can reach out to rural communities as well." The first telethon was held in 2010.