The stock exchange's broad OMXS index closed 1 percent down on Friday after some recovery in the afternoon; the index had been up during the morning.
This represents a decline of 5.2 percent during the week as a whole.
Friday's drop came as oil prices continued to surge. After rising 6.3 percent during the day, a barrel of North Sea oil was $90.85. U.S. WTI oil rose 9.2 percent to $88.45.
This morning, Qatar's energy minister also warned that the Iran war could push oil prices much higher within just a few weeks.
In addition, unexpectedly weak job statistics in the US caused the fall in Stockholm to deepen.
Defense group Saab, up 3.9 percent, bucked the trend on the OMXS30 index and was the most traded stock in Stockholm. Only six of the 30 stocks on the large-cap list rose.
At the close in Stockholm, the stock exchanges in Frankfurt, London and Paris were also clearly down, as were all three major indices on the New York Stock Exchange.
