Illegal securities activities refer to the acts of publicly issuing securities, setting up securities exchange places or securities companies, engaging in securities brokerage, securities underwriting, securities investment consulting and other securities businesses without the approval of the competent authorities in violation of the provisions of the Securities Law and other laws and regulations. Mainly divided into illegal issuance of securities, illegal establishment of securities trading places or securities companies and illegal operation of securities business.

There are many kinds of illegal securities activities, the most important feature of which is fraud. Criminals take advantage of investors' psychology of wanting to make big money, make quick money or even get rich overnight, falsely claiming that they have inside information, and can provide big bull stocks and other means to defraud investors of high information fees and membership fees. What's more, criminals set up a black market for securities and set up original stock scams. Cheat money. The behavior of criminals mostly constitutes fraud, and even serious violation of criminal law constitutes a crime.