Iron oxide-loaded hydrous potassium tetratitanate (K 0.3Ti 4O 7.3(OH) 1.7) compounds consisting of 1.48 wt% (sample 'B'), 1.87 wt% (sample 'C') and 5.60 wt% (sample 'D') of iron oxide were synthesized by suspending the K 0.3Ti4O 7.3(OH) 1.7 (sample 'A') in Fe 2(SO 4.3 solution for 24 h, followed by washing several times with deionized water and then dried at 120 °C for 24 h. The K 0.3Ti4O 7.3(OH) 1.7 was synthesized by refluxing the K 2Ti 4O 9 2H 2O in 1 M HNO 3 solution. Band-gap energies of the K 0.3Ti4O 7.3(OH) 1.7 and the iron oxide-loaded samples are 3.12 ± 0.6 eV and 2.23 ± 0.09 eV, respectively. Photooxidation activity towards methylene blue decomposition under fluorescence irradiation was found to decrease as follow: sample 'B' > sample 'C' > Sample 'A' > sample 'D' > commercial Fe 2O 3 ∼ Blank. The photoactivity under sunlight irradiation was found to decrease as follow: sample 'B' > sample 'A' > Sample 'C' > sample 'D' > commercial Fe 2O 3 ∼ Blank. Keywords: Potassium Tetratitanate, Methylene Blue, Photooxidation, Fluorescence, Sunlight. Copyright © 2012 American Scientific Publishers All rights reserved.