1) Tawheed (oneness of God)
Means that ALLAH(s.w.t) is One.  He has Neither any colleague nor any partner.  He is neither born
of any parent nor has He any wife, children or relatives.

2) ADDEL(Justice of God)
He is not a tyrant. Everybody's awards will depend upon his deeds. He who obeys His commands will be awarded a place in paradise and he who disobeys Him (ALLAH) will be sent to Hell.
In this connection Quran says:
ALLAH affirms that there is no God but he : and so do the angles and these endued with knowledge. He is standing firm in justice.    3:18

3) Nubuwwat (Prophethood)
The conception of Prophethood follows from the premises that it is the will of ALLAH that every human being should pursue a defiend code of life and follow certain principles of conduct ALLAH therefore had to send prophets to acquaint the humanity with these principles and the code of life.
Quran says:
Nor would We punish without sending Messengers to give warning.
The third Usool "NUBUWWAT" calls for belief in all the prophets sent by ALLAH from time to time for the guidance of humanity. According to Islam, ALLAH sent 1,24,000 prophets in all. ADAM was the first of them. NUH, IBRAHIM (Abraham), MUSA (Moses) and ISA (Jesus) were other prominent prophets (peace be on them all). Our Prophet Hazrrat Muhammad Mustafa (S.A.W.W) was the the last. Some  prophets came with Shari'ats (Codes of life),while other merely propagated the Shari'ats of their fore-runners. Since the words of prophet are to be obeyed and his actions are to serve as guide, it follows that every prophet should be Infallible in his thoughts, words and deeds.

4) MAMAT (Vicegerency of the Prophet)
During his life time, Prophet Muhammad (S.A.W.W) had announced on several occasions that the reponsibility of the guidance of the muslim community would devolve after him on certain named persons as ordained by ALLAH. These persons are known as Imams (Vicegerents of the Prophet). The Imam deputises the Prophet in very respect. Like the prophets, therefore the Imam should also be Infallible in his thoughts, words and deed.
There are clear references in the Holy Quran:
O ye who believe ! Obey ALLAH and obey the Messenger and these among you invested with Divine Authority; and if in aught ye differ, bring it before ALLAH and the Messenger if ye believe in ALLAH and the Latter Days. This is the best and the fairest way of settlement. 4:59

5) Qayamat (Resurrection)
There is a life Hereafter. After death an individual gets the reward or punishment of the deeds performed before death. For this purpose on a certain day called the day of judgement, all the dead would be resurrected from their graves and Heaven or Hell depending on the merits of their actions in this world.
The Holy Quran says:
Beware when the Event (Qayamat) would occur
No soul would then falsify its occurence
(Many) will it bring low When the earth would be shaken to its depths,
And the mountains would be completely crumbled becoming dust scattered all about. 56:1-6
The day of Qayamat will be of 50,000 year's duration as has been written in the Holy Quran. The sun on that day will come down very low and the earth will be red-hot like heated copper.