Qutb-ud-din Mubarak Shah Khilji (Urdu: قطب الدین مبارک شاہ, Hindi: क़ुतब उद्दीन मुबारक शाह) (died June 1320) was the third ruler of the Khilji dynasty in Sultanate of Delhi, India. Qutb-ud-din Khilji was the son and successor of Alauddin Khilji.
Qutb-ud-din, at the age of 18, was originally appointed regent to his younger six-year-old brother, the king. Within two months, Qutb-ud-din blinded his brother and ascended the throne. He began his rule by releasing thousands of prisoners and abolishing all taxes and penalties imposed by his father. Qutb-ud-din Mubarak Shah was the weakest ruler of the dynasty.
Qutb-ud-din was murdered by Khusro Khan in 1320, which ended the Khilji dynasty. Khusro Khan was a former Hindu slave of the Bawariya Hindu caste in Gujarat.