The concept of aggregation-induced emission (AIE) was first introduced by BenZhong Tang in 2001. In the past decade, different AIE systems have been designed andstudied, and have been utilized broadly as chemical sensors, biological probes andimmunoassay markers. However, there are no reports on AIE effects for water solubleβ-diketone derivatives, which are also found to exhibit cellulose-specific fluorogenic emissionpresumably caused by AIE effects. In a previous study, we synthesized a class of pyridinesubstitutedβ-diketone molecules and discovered that one of them possesses interesting AIE.Here we focus on this particular β-diketone molecule,1-(2-hydroxyethyl)-3-(3-(4-methoxyphenyl)-3-oxopropanoyl)-pyridin-1-ium bromide, whichwas synthesized via Claisen consendation. The optical properties of the molecule were studied.We found that it is non-emissive in aqueous solution but becomes highly fluorescent when itis in the solid state. Fluorescent spectra of the molecule in different organic solvents weremeasured. In addition, the molecule also exhibits cellulose-specific fluorescence turn-onbehaviors. Cotton, filter paper, textiles and plants rich in cellulose show a dramaticfluorescence increase when they are exposed to the diketone compound in water. Theadsorption is strong and cannot be removed by simple washing. The aqueous solution of theβ-diketone can also label cells and can be sensitive to pH. The β-diketone molecule ispromising in biological sciences such as cellulose imaging in live cells and textile engineeringsuch as fluorescent fiber coloration.