Two cokes prepared from coals of different ranks were subjected to gasification and annealing under the simulated blast furnace (BF) conditions. The changes in coke petrography were studied using techniques and algorithms developed by Pearson Coal Petrography, Inc.; the coke microstrength was measured using ultramicro indentation. Gasification under the simulated BF conditions consumed both reactive maceral-derived components (RMDCs) and inert maceral-derived components (IMDCs) at the lump periphery; however, the degradation did not penetrate to the core of the coke lump during gasification. The annealing at 2000 degrees C after gasification further promoted the degradation of IMDCs and RMDCs located at the lump surface; the degradation penetrated toward the center of the coke lump during annealing. The consumption of the coke matrix in the lump core mainly concentrated on the IMDC microtexture, but the RMDC microtexture generally remained. Under the simulated BF gasification conditions, both bireflectance and maximum reflectance of cokes decreased; the more significant value decrease was determined on the coke made from higher rank coal. The inclusion of H-2 into the gasification atmosphere caused lower bireflectance reduction for both cokes; however, this mitigation effect caused by the addition of H-2 during gasification was overwritten by the subsequent high-temperature annealing, which returned similar bireflectance of cokes upon annealing after gasification in the different atmospheres. The annealing at 2000 degrees C after gasification significantly promoted the coke reflectance loss and enlarged the differences between the cokes from different coal precursors. Upon simulated BF gasification and annealing conditions, the degradation of coke microstrength and reflectance loss took place simultaneously as a result of the rearrangement of the coke microstructure and the change of coke morphology.