Ratcheting and creep of reinforced graphite sheet with stainless steel insert (RGSWSSI) are tested under cyclic stress‐controlled compression by a self‐designed clamp from 500°C to 600°C. The effects of insert type, temperature, stress amplitude, stress rate, creep, and loading sequence are considered. Results present that ratcheting deformations for RGSWSSI with 316‐L stainless steel tanged and bonded insert approach to each other and show little rate dependence, while they slightly increase with the increment of stress amplitude and temperature. Moreover, obvious ratcheting effect takes place under cyclic pulsating loads with the peak stress of 32 MPa at 500°C or higher. The accumulated deformations of RGSWSSI under small stress amplitude only increase during about the first 25 cycles and then always turn to shakedown. It can also be estimated by the corresponding static creep strain in practical engineering with good accuracy at high temperature. This work provides important data and understanding of RGSWSSI under harsh fluctuating loads.