It is great significance to develop an effective eye-readable gas detection technology that would be safe, low-cost, and highly sensitive, serving as a vital complement to traditional H-2 sensors. In this work, a class of flexible MoO3 nanowire labels (NWLs) modified with Pd nanoparticles have been successfully developed and studied as eye-readable hydrogen indicators at room-temperature. The nanowire labels turn from white to blue-gray even at a very low concentration (0.1%), where the eye-readable color change takes place in 65 s, and the color changes gradually from white to blue-gray. The reaction of MoO3 nanowire label with hydrogen is of high sensitivity, fast response and time-resolved. The process can be divided into two stages, i.e., fast and slow responses, which are dominated by H-2 concentration and intrinsic properties of Pd-MoO3, respectively. The color response is also reversible by annealing under air ambient at 200 degrees C for 2 h, and selective to hydrogen compared with other flammable gases (i.e., CO, CH3CH2OH, CH3OH). The gasochromic NWLs involve Pd-catalyzed reduction of MoO3 in the presence of hydrogen. They also exhibit the superior advantage of being flexible, which have promises applications in efficient eye-readable hydrogen detection.