"A few days ago I spoke to Crown Prince Salman and enquired about King Abdullah's health. News of King Abdullah's passing away is saddening," the prime minister tweeted.
"In King Abdullah, we have lost an important voice who left a lasting impact on his country. I condole his demise," he said.
The prime minister said our thoughts are with the people of Saudi Arabia during this hour of grief.
King Abdullah's death was announced on Saudi state TV at 1 am today.
President Pranab Mukherjee also condoled the death of King Abdullah of Saudi Arabia, remembering him as one who had "genuine warmth and affection" for India.