The invention provides a method, a system and an application for real-time evaluation of fund assets based on a distributed data stream. On the basis of horizontally expanding basic computing resources, the system and its application can stably and quickly import and process a large amount of fund asset data, which is a real-time calculation, and can meet the requirements of completing the valuation accounting of all fund assets within 3 seconds for 10,000 products, and simultaneously output the key index data such as net asset value, unit net value, paid-in capital, and so on. The invention solves the problem that the fund manager can not obtain the fluctuation of the fund net asset value in real time, and enables the user to obtain the real-time net asset value of the fund immediately after the fluctuation of the market and the investment of the fund manager. As that method and system of the invention are used, the investment personnel can timely and accurately perceive the investment result of the fund in the daytime, the fund manager can immediately perceive the change of the net value of the fund aft the investment, and can obtain the feedback net value of the fund. A method and system of that present invention.