The work aims to study the solid solution nitriding behavior of TP304L stainless steel during short-time high- temperature treatment in N2 atmosphere. Nitrided tubes and non-nitrided tubes were prepared by short-time high-temperature heat-treatment with N2 and Ar as protective atmospheres. SEM-EDS and XPS were used for microstructure observation and composition analysis. Vickers Indenter was used to measure the surface hardness, and the corrosion resistance was compared through intergranular corrosion test and electrochemical pitting corrosion test. Compared to non-nitrided tubes, the average surface hardness of the nitrided tube increased by 30HV0.1. The content of N element on the surface of the nitrided tube was increased, and the penetration depth of N was about 2 μm. No nitride compounds were found by SEM. The analysis of element valence state by XPS indicated that the N atoms formed Fe-N bonds, which mostly corresponded to α″-Fe16N2/α′-Fe8N, as the form of solid solution and supersaturated solid solution. Cr-N bond was undetectable, indicating that there is no harmful Cr2N phase. The electrochemical pitting potential of nitrided tubes increases by 20~100 mV, with improved pitting resistance, and its resistance property of intergranular corrosion was equal to non-nitrided tubes. In summary, the short-time high-temperature heat-treatment of TP304L stainless steel in N2 atmosphere caused solution nitriding behavior, which improved the surface hardness and corrosion resistance, without the precipitation of Cr-N or Fe-N phase.