AbstractWe have designed and developed a tetraphenylethen (TPE)‐anthracene‐(aminomethyl)phenylboronic acid ester (AminoMePhenylBPin) structure RN‐1 possessing PET (photo‐induced electron transfer) and AIEE (aggregation‐induced emission enhancement) characteristics as a fluorescent sensor for detection of water in organic solvents. It was found that the appearance of fluorescence band in the low water content region is attributed to the fluorescence emission originating from the anthracene skeleton due to the formation of PET inactive species RN‐1(H2O) by the addition of water molecules. Moreover, the appearance of broad fluorescence band in the high water content region is attributed to the AIEE characteristic due to restricted intramolecular rotation (RIR) of TPE unit associated with the aggregate formation (RN‐1(H2O)‐A). This work proposes that the PET/AIEE hybrid fluorescence sensor can act as a dual‐fluorescence emission sensor for detection of water in low water content region and high water content region in solvents.