David Martin, a father-of- three, died when his Audi car was blown off the road and burst into flames at Killdress, near Cookstown.
Mr Martin, 33, was returning to his home at Pomeroy after spending the night at a friend's house. Police said the bomb was placed under his car during the night.
He was the 27th victim of violence in Ulster this year.
His widow, Hilda, said: 'We believe he was targeted simply because he was a hard-working Protestant who had hopes to build a good and successful future for his family in this area.
'The family would not wish anyone else to go through the heartbreak we ourselves are enduring and call for no retaliation.'
A police spokesman said: 'This was a vicious murder by faceless cowards who used the cover of darkness to seek out their victim.'
Albert Reynolds, the Irish Prime Minister, yesterday strongly criticised the IRA's continuing violence. He said: 'I have consistently condemned all violence and the death and destruction that has taken place. I believe violence is the road to nowhere.' He added that it was important that all-party talks on the future of Northern Ireland resumed as soon as possible.