The fluorescent detection of nitrite ions has been challenging owing to the poor acid-stability of typical fluorescent probes. Herein, an acid-inert rhodamine-based fluorescent probe has been developed for the fast detection of trace amount of nitrite ions with turn-on mode. The detection limit of nitrite ions was determined to be 9.4 nM (S/N = 3) and the linear range with high linear correlation was observed between 0.025 to 2.5 μM. A test paper method was developed for rapid visual detection of nitrite ions. Quantitative analysis of two real water samples also confirmed the reliability and sensitivity of the developed fluorescent method.