"The index lost around 150 points as investors were more cautious, especially foreign investors who had snapped up stocks in the last one week," Intikhab Ahmed, an analyst with Capital Investments, said.
The loss of points is not surprising because the stock market was having a bull-rush for the 11 consecutive days, he added.
Muslim Commercial Bank Ltd and Oil and Gas Development Company Ltd saw some correction after rallying for several days.
"MCB stocks today fell by 4.68 per cent to Rs 275 and Oil and Gas was down 0.22 per cent to Rs 211.25," he said.
"With the more serious work of the government to be formed and the tough challenges that lie ahead for the new government there is more caution now among the investors," trader said.
In the currency market, the Pakistani rupee ended weaker at 98.50 against the dollar, compared to Wednesday's close of 98.45.