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Abstract Increase photorespiration and optimising intrinsic water use efficiency are unique challenges to photosynthetic carbon fixation at elevated temperatures. To determine how plants can adapt to facilitate high rates of photorespiration at elevated temperatures while also maintaining water‐use efficiency, we performed in‐depth gas exchange and biochemical assays of the C₃extremophile,Rhazya stricta. These results demonstrate thatR. strictasupports higher rates of photorespiration under elevated temperatures and that these higher rates of photorespiration correlate with increased activity of key photorespiratory enzymes; phosphoglycolate phosphatase and catalase. The increased photorespiratory enzyme activities may increase the overall capacity of photorespiration by reducing enzymatic bottlenecks and allowing minimal inhibitor accumulation under high photorespiratory rates. Additionally, we found the CO₂transfer conductances (stomatal and mesophyll) are re‐allocated to increase the water‐use efficiency inR. strictabut not necessarily the photosynthetic response to temperature. These results suggest important adaptive strategies inR. strictathat maintain photosynthetic rates under elevated temperatures with optimal water loss. The strategies found in R. stricta may inform breeding and engineering efforts in other C₃species to improve photosynthetic efficiency at high temperatures.