Anaerobic digestion (AD) can act a waste-to-energy technology, using commonly available residues (e.g. from agriculture or food production) to produce biogas. Biogas consists basically of methane and carbon dioxide, and can be used as renewable energy source to produce electricity and heat. The process itself comprises four phases that are closely interwoven, namely hydrolysis, acidogenesis, acetogenesis and methanogenesis. Methanogenesis, the last step of AD, is a complex bioprocess, which needs a stable or adaptable archaeal community in order to run smoothly. When using agricultural residues, e.g. cattle manure, biomethanisation is commonly conducted under mesophilic (37C) or thermophilic (55C) conditions.This study focused on the specific effect of temperature on anaerobic digestion and evaluated its influence on gas yield as well as on the microbial community composition and methanogenic activity. A special focus was laid on the temperature in between mesophilic- and thermophilic conditions. Therefore, three different temperatures (37 C (MES), 45 C (GAP) and 55 C (THERM)) were compared in a long- term biomethanisation experiment (171 days) with lab-scale bioreactors (2 L; fed-batch) using the substrate cattle manure and corn straw (1:200 (w/w)). The experimental set-up concentrated on linking physicochemical analyses, theoretical biogas potential calculations and molecular community analyses (microarray (ANAEROCHIP), specific methanogenic activity test (SMA)).The focus was laid on the adaptive behaviour of the methanogenic community with a special interest on community dynamics and -activity.In detail, the SMA test evaluated, which pathway of methanogenesis was active over time at different temperatures and at the same time the community transition was monitored with the ANAEROCHIP.The findings showed, that temperature significantly affected the methanogenic community. The atypical temperature of 45 C exhibited perfect process stability and highest biogas yields.Adding up methane yields of all SMA test-substrates (acetate, propionate, butyrate, H2/CO2), methane production at GAP was marginally higher than THERM and almost twice as high as MES. Furthermore at 37 and 45 C, a change from hydrogenotrophic- to acetoclastic methanogenesis was observed, whereas the trend was opposite at 55 C. Our findings support, that the GAP conditions exhibit high reactor stability and -activity.Additionally, in contrast to other studies, GAP and THERM treatments had a metabolically more diverse methanogenic community, than MES. Methanomicrobiaceae was the dominating methanogenic family in all treatments, although at varying abundance at MES, GAP and THERM. A detailed cost- and energy balance calculation and hygienisation test shall reveal the additional benefit of increasing the temperature from MES towards GAP.