Amorphous polymer-basedroomtemperaturephosphorescence (RTP) materials exhibitingtunableemission colors have received tremendous attention and are extremely challenging to prepare. Herein, polyacrylamide-based RTP materials withtunablemulticoloremission were prepared via copolymerizing phosphor with concentration dependent luminescence colors and acrylamide with different molar ratios. The hydrogen bonding interactions and chemically crosslinked structures in thesepolymerseffectively restrict the mobility of phosphors and activate efficient RTP emission. The molar ratio of phosphor and acrylamide has a significant influence on the photophysical properties of thesepolymers, which can be used to fabricatemulticolormaterials. In addition, the RTP intensity decreases with increasinghumiditydue to the disassociation of hydrogen bonding by adsorption of water, manifesting as ahumiditysensor. Benefiting from the distinguishable RTP lifetimes and the responsiveness tohumidity, triple encodingforinformationencryptionis successfully realized.