Wall Street also fell at the opening. The market is nervous about US statistics later in the week and the cryptocurrency bitcoin was among the punching bags. By 5:30 p.m., Bitcoin had fallen to nearly $84,800 per bitcoin.
Defense group Saab has taken an order for mobile air defense from Lithuania. But the share fell just over 2.7 percent – in company with most European defense stocks.
Other OMXS30 stocks that took a beating were Wallenberg Sphere's venture capital company EQT, which fell 2.1 percent, and automation group ABB, which fell 1.1 percent.
Clothing giant H&M went the other way, up 2.8 percent.
With Monday's decline, the Stockholm Stock Exchange's OMXS index has risen 6.8 percent since the turn of the year.
The leading European stock exchanges also fell. The declines in London and Paris were on par with the Stockholm Stock Exchange, while Frankfurt fell more.
