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Low temperature catalysts are attracting increasing attention in the selective catalytic reduction (SCR) of NO with NH3. MnOx-decorated MgAl layered double oxide (Mn/MgAl-LDO) was synthesized via a facile fast pour assisted co-precipitation (FP-CP) process. Compared to the Mn/MgAl-LDO obtained via slow drop assisted co-precipitation (SD-CP) method, the Mn/MgAl-LDO (FP-CP) has excellent activity. The Mn/MgAl-LDO (FP-CP) cat-alyst was shown to possess a high NO conversion rate of 76％–100％from 25 to 150 °C, which is much better than the control Mn/MgAl-LDO (SD-CP) (29.4％–75.8％). In addition, the Mn/MgAl-LDO (FP-CP) offered an enhanced NO conversion rate of 97％and a N2 selectivity of 97.3％at 100 °C;the NO conversion rate was 100％and the N2 selectivity was 90％at 150 °C with a GHSV of 60,000 h?1. The Mn/MgAl-LDO (FP-CP) catalyst exhibited a smaller fragment nano-sheet structure (sheet thickness of 7.23 nm). An apparent lattice disorder was observed in the HRTEM image confirming the presence of many defects. The H2-TPR curves show that the Mn/MgAl-LDO (FP-CP) catalyst has abundant reducing substances. Furthermore, the enhanced surface acidity makes the NH3 con-centration of the Mn/MgAl-LDO (FP-CP) catalyst lower than 100 ml·m?3 after the reaction from 25 to 400 °C. This can effectively reduce the ammonia escape rate in the SCR reaction. Thus, the Mn/MgAl-LDO (FP-CP) catalyst has potential applications in stationary industrial installations for environmentally friendly ultra-low tempera-ture SCR.