Sefton Central Labour MP BIll Esterson said Twitter and other social media was now a "crucial way for MPs to interact with more people".
Bill said social media was an important tool for to create links between many people who may not otherwise engage with party politics and their MPs.
Bill joined Twitter shortly after being selected for Sefton Central.
The MP said: "As elected parliamentary representatives, we have a duty to make sure we communicate with all of our constituents. That includes via traditional methods, like letters and leaflets, through to new media techniques like Facebook and Twitter.
"What I like about social media is that it creates what is essentially a one to one with me and constituents. I can not only tell people what I am working on, but I can also directly communicate with individuals and groups of people at the same time.
"If they flag something up to me, I can respond and take action.
"It means that as well as dealing with concerns and issues raised with me via letter, phone call, through my surgeries and via visits to my office, people can also contact me via social media."
Bill said he has found social media particularly effective in engaging young people.
Bill said: "I do a lot to engage people in politics throughout Sefton Central. I spend a lot of time listening to people's concerns and issues on the doorstep here in Sefton Central and I am also currently running a series of People's Politics Inquiry meetings throughout Sefton Central where I try and find out how we can better engage people.
"But what is particularly difficult is engaging young people. How can we get more young people to take an interest in politics, in their local community, in the issues that effect them day in and day out?
"Twitter and Facebook are two effective tools to do just that. Young and old alike who are on Twitter or Facebook can contact me directly.
"I can tell them what I am working on. I can tell them what issues are coming up in Parliament. They in turn can tell me their views.
"And as we have seen, Twitter can be used as a platform for campaigns. Not too long ago, there were hundreds of thousands of people on Twitter explaining why #welovetheNHS after Tory MEP Daniel Hannan said our National Health Service was a '65 year mistake'.
"The number of people who took to Twitter to criticise the Tory's viewpoint showed the strength of feeling that people have for our NHS.
"That is the effectiveness of social media. If gives people the chance to directly communicate with their elected representatives and it allows people to directly shape the debate and make a real change.
"That's why I am on Twitter and why I encourage other to join it too."