Trust companies can only engage in the asset business of trust, and cannot be the intermediary of stock trading, while securities companies are aimed at the business of stock market.

Trust company is a multilateral credit behavior based on trust entrustment, in the form of managing monetary funds and physical property, integrating financing and integration. It appears with the development of commodity economy. Trust business appeared in Britain in the18th century. Trust business mainly includes two aspects: entrustment and agency. The former means that the property owner entrusts his property to others for the benefit of himself or his designee, and requests to properly manage and operate it for a certain purpose; The latter refers to some economic affairs that one party authorizes the other party to handle on its behalf. Trust business involves three parties: the principal, the trustee and the beneficiary. The person who transfers the property right, that is, the original owner of the property right is the principal; The person who accepts the entrustment to manage and operate the property on his behalf is the trustee; Those who enjoy property benefits are the beneficiaries. There are many kinds of trusts, including personal trust, legal person trust, arbitrary trust, special trust, public trust, private trust, self-interest trust, other benefit trust, capital trust, movable property trust, real estate trust, business trust, non-business trust, civil trust and commercial trust. Trust business is flexible and adaptable, which is conducive to invigorating the economy and strengthening economic and technological cooperation between regions; It is conducive to absorbing domestic and foreign funds and supporting the equipment renewal and technological transformation of enterprises.

Securities companies are intermediaries for investors to participate in the stock market. A stock exchange is a place where stocks are traded. Because ordinary investors can't enter the exchange to trade, and securities companies only have seats in the exchange, ordinary investors must trade stocks through securities companies. Securities companies only charge fees.