Secretary of State for Scotland Alister Jack registered £70,000 worth of shareholdings two years ago in a private equity group linked to weapons makers.
Arms firms due to attend a trade event dubbed a “festival of violence” gave MP's more than £60,000 in donations.
Serco, a firm evicting hundreds of asylum seekers from their homes in Glasgow, will be exhibiting at a controversial arms trade show.
The UK government has been condemned for arming states named in a UN report revealing that 12,000 children were killed or maimed last year in armed conflicts.
Bombs and missiles will still be exported to Saudi Arabia under a secretive licensing system despite a court ruling that UK arms sales are illegal.
American multinationals Raytheon and Lockheed Martin are bidding for a lucrative Ministry of Defence training contract at Faslane.
The UK government broke the law by selling arms to Saudi Arabia, the Court of Appeal says in a landmark ruling.
Dozens of companies have undergone human rights checks by Scottish Enterprise following concerns over public money being awarded to arms firms through business grants.
Arms firms supplying weapons for the war in Yemen that has killed 70,000 people were handed nearly £3m by the Scottish Government last year.