In recent years, the photothermal evaporation technology effectively solves the problem of fresh water shortage has attracted great interest, but the problem that Volatile Organic Compounds (VOCs) always enters the condensate with vapor during the evaporation process, so the combination of photothermal evaporation and photocatalysis is considered. In this paper, narrow band gap β‐MnO2 is selected as the material for photothermal evaporation and catalysis (PEP), and a β‐MnO2 porous hydrogel (β‐MnO2‐PH) interfacial evaporator with high evaporation efficiency and catalytic degradation of organic pollutants is designed using porous and hydrophilic hydrogels as carriers. The optimized evaporation rate can reach 3.5 kg m‐2 h‐1 and achieve high light absorption of 93.4% in the full spectral range. This is better than the performance of most MnO2‐based solar evaporator reported so far. In additions β‐MnO2‐PH has the function of photocatalytic purification and effectively degrades VOCs such as phenol. By combining photothermal action of evaporator with photocatalytic performance, it provides unlimited potential application in solar desalination, industrial wastewater treatment.This article is protected by copyright. All rights reserved.