Many people would answer the above question with a single word—God. But significantly, nowhere does the Bible say that either Jesus Christ or his Father are the real rulers of this world. On the contrary, Jesus said: "The ruler of this world will be cast out." And he added: "The ruler of the world is coming. And he has no hold on me."—John 12:31; 14:30; 16:11.
There is no need to guess at the matter, for the Bible clearly shows that an intelligent, unseen person has been controlling both men and nations. It says: "The whole world is lying in the power of the wicked one." And the Bible identifies him, saying: "The one called Devil and Satan . . . is misleading the entire inhabited earth."—1 John 5:19; Revelation 12:9.
Let's consider a few points which shows that satan is the ruler of this world.
Point one, In the Bible book of Matthew 4:8-10, Satan the devil showed Jesus all the glories of the world and promised to give it to Jesus if he worship him. Think about this. would Satan had offered Jesus "all the kingdoms of the world" if the world is not his? No, he would not.
Point two, in the Bible book of 2Corinthians 4:4, we were told that the "god" of this system of this has blinded the mind of unbelievers so that they might not know Jehovah
Point three, Remember that Satan had been an angel created by God, but he became envious of God's position. He challenged God's rightful rulership. To this end he used a serpent as a mouthpiece to deceive the first woman, Eve, and was thus able to get her and her husband, Adam, to do his bidding rather than obey God. (Genesis 3:1-6; 2 Corinthians 11:3) He also claimed he could turn all of Adam and Eve's yet unborn offspring away from God. So God allowed time for Satan to try to prove his claim, but Satan has not succeeded.—Job 1:6-12; 2:1-10. With him ruling the world today are some of the angels he decieved from heaven down to the vicinity of the earth.
Do you believe Satan is the ruler of the world?