Praise be to Allah.
Blowing oneself up is suicide, which is haraam (forbidden) because Allah, may He be exalted, says (interpretation of the meaning): “And do not kill yourselves” [an-Nisa’ 4:29]. And the Prophet (blessings and peace of Allah be upon him) said: “ … “Whoever kills himself with a piece of iron will have that iron in his hand, thrusting it into his belly in the Fire of Hell for ever and ever.” Narrated by al-Bukhaari, 5442; Muslim, 109.
This cannot be compared to the child in the story of al-Ukhdood (the ditch), because he did not kill himself; rather he was killed by the disbelieving king. And it cannot be compared to the story of al-Bara’ (may Allah be pleased with him) being thrown over the wall (to open the gates of the fort), or the hadeeth about charging into the midst of the enemy, for the same reason. In those cases there was the possibility of surviving, unlike when a person blows himself up. Moreover, such operations sometimes result in the death of a person for no benefit or very little benefit, or they cause the death of innocent people.
This is what has been stated in fatwas by a number of senior contemporary scholars. The great scholar Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allah have mercy on him) was asked: What is the ruling on one who blows himself up in order to kill a number of people?
He replied:
What I think, and I have pointed out on more than one occasion, is that this is not acceptable, because it is killing oneself, and Allah says (interpretation of the meaning): “And do not kill yourselves” [an-Nisa’ 4:29]. And the Prophet (blessings and peace of Allah be upon him) said: “Whoever kills himself with something will be punished with it on the Day of Resurrection.” Narrated by al-Bukhaari, 5700; Muslim, 110.
Whoever kills innocent person has killed the whole mankind (Holy Quran)
Suicide bombing and killing innocent people are prohibited, forbidden and unlawful in Islam
Terrorism in Kashmir and other parts of the world is Haram according to Quran and Sunnah