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Lysosome visualization is very important for accurate diagnosis of human diseases. However, currently developed lysosome imaging probes usually have poor specificity and are easily quenched, leading to a low signal to noise ratio in lysosome labeling. To resolve this problem, herein, metal–organic framework-based probes of copper–terephthalic acid (CuBDC) are investigated, which show sensitivity to pH and hydrogen peroxide (H2O2), simultaneously. By self-assembling under the template effect of soluble starch, the particle size of CuBDC can be well controlled for entering into cells and locating lysosomes. Based on the Fenton-like reaction, CuBDC can catalyze the decomposition of H2O2 into ˙OH, which in turn reacts with CuBDC to generate a stable fluorescent substance. Meanwhile, Cu2+ can be released from CuBDC under acidic conditions for reacting with H2O2 more thoroughly. And the synthesized CuBDC has a similar attraction to the electrophilic ˙OH at different pH values owing to the residual soluble starch in the particles. The above properties cause CuBDC to have a stable fluorescence signal with low pH values and high H2O2 concentration, simultaneously. The fluorescence imaging experiments in HeLa cells demonstrate that CuBDC acting as a pH/H2O2 responsive fluorescent probe holds great promise for lysosome-specific imaging. [ABSTRACT FROM AUTHOR]