Southwest Securities International Securities Limited, together with its subsidiaries, provides various financial services in Hong Kong. It operates through Brokerage and Margin Financing, Corporate Finance, Asset Management, and Proprietary Trading segments. It acts as financial advisor for mergers and acquisitions, reorganizations, general offers, acquisition financing, and private equity transactions; and a compliance and independent financial adviser.

The company also offers debt products, including investment-grade, high-yield, convertible, preferred stock, and panda bonds; equity capital market services; and asset management services and advice on securities for corporations, institutions, and high-net-worth individuals. In addition, it is involved in the stock brokerage, securities margin financing and underwriting, subscription of initial public offering, placement of shares, local and overseas bonds brokerage, and exchange traded fund activities, as well as the trading of real estate investment trust, stock warrants, stock options, and CBBCs. Further, the company offers consultation and trading services in the futures market, as well as custodian services; cash management and financing, investment management, wealth planning, and insurance planning services; investment products, such as equity, fixed income, and alternative assets; insurance products; and investment immigration services.

Additionally, it distributes unit trusts, mutual funds, investment- linked, and mandatory provident fund products; and provides financial consulting and planning, and insurance broking services. The company was formerly known as Tanrich Financial Holdings Limited and changed its name to Southwest Securities International Securities Limited in May 2015. The company was founded in 1990 and is headquartered in Hong Kong, Hong Kong.

Southwest Securities International Securities Limited operates as a subsidiary of Southwest Securities International Investment Company Limited.