In the present work, potato-like silver molybdate (Ag2MoO4) microstructures were synthesized through a simple hydrothermal method. The microstructures of Ag2MoO4 were characterized by various analytical and spectroscopic techniques such as XRD, FTIR, Raman, SEM, EDX and XPS. Interestingly, the as-prepared Ag2MoO4 showed excellent photocatalytic and electrocatalytic activity for the degradation of ciprofloxacin (CIP) and electrochemical detection of hydrogen peroxide (H2O2), respectively. The ultraviolet-visible (UV-Vis) spectroscopy results revealed that the potato-like Ag2MoO4 microstructures could offer a high photocatalytic activity towards the degradation of CIP under UV-light illumination, leads to rapid degradation within 40 min with a degradation rate of above 98%. In addition, the cyclic voltammetry (CV) and amperometry studies were realized that the electrochemical performance of Ag2MoO4 modified electrode toward H2O2 detection. Our H2O2 sensor shows a wide linear range and lower detection limit of 0.04–240 μM and 0.03 μM, respectively. The Ag2MoO4 modified electrode exhibits a high selectivity towards the detection of H2O2 in the presence of different biological interferences. These results suggested that the development of potato-like Ag2MoO4 microstructure could be an efficient photocatalyst as well as electrocatalyst in the potential application of environmental, biomedical and pharmaceutical samples.