Abstract: Coding is the key of integrating scattered and complicated data.In the process of systematically integrating national environmental function zone data(map & table) for various provinces,the authors analyzed the advantages and disadvantages of river coding of European countries and USA as well as of different departments in China,such as water conservation and surveying and mapping.Considering the inadequacy of original water environmental function zone coding and borrowing experience from international society in river coding,a new-type coding having 14 digit number-letter mixed code,suited for the environmental function zone,was proposed.The code is composed of 6 digit numeric administration code(GB2260-1995),6 digit number-letter mixed river name code used in(1∶250 000)-scale digital map and 2 digit numeric sequence code that uniquely identifies each environmental function zone and links table data with maps.However,the code is not very perfect,as the data structure of(1∶250 000)-scale digital map is ’polyline’ & ’polygon’ and not ’route’ network,and the code cannot reflect the attributes of length or length proportion of function zones.It could be improved using the USA’s national hydrography dataset advanced experience for reference.