Abdullah al-Qasemi (1907 – 9 January 1996; Arabic: عبدالله القصيمي) was a Saudi Arabian 20th-century writer and intellectual.

He questioned the existence of God and criticized religions, which resulted in the allegations of him becoming an atheist, therefore his books were banned all over the Arab world.

The merchant Abdulaziz Al-Rashed Al-Humaid was impressed by al-Qasemi, so he took him to Iraq, India and Syria, finally, Al-Qasemi resumed his studies at the Sheikh Amin Shanqeeti school in Zubair in Iraq after then he traveled to India where he spent two years learning in school, he learned Arabic, hadiths, and the foundations of the Islamic Sharia, he then returned to Iraq where he joined al-Kazimiyah school, he returned to Damascus, finally, he decided to live in Cairo.

Al-Qasemi has studied at the Al-Azhar University in Cairo in 1927, but he was soon expelled because of his book "The Najdi Lightning Sweeping al-Degwy's Darnkess" Arabic: البروق النجدية في اكتساح الظلمات الدجوية, which he had written in response to an article by Al-Azhar scholar Yusuf al-Degwy Arabic: يوسف الدجوي, entitled "The litigiousness and ignorance of Wahhabists" published in the Journal "Nour al-Islam" in 1931.

[citation needed] After his expulsion from al-Azhar, al-Qasemi changed his way of thinking, defending secularism and scepticism and criticizing religion to the point where his opponents labelled him "atheist".