Bituminous coals from 5 Polish mines and binary coal blends (60 samples) were tested for coking behaviour and coke properties. In particular, coke reactivity index, coke strength after reaction, coke quality and catalytic index were detd. A linear additivity of coke quality was obsd. in the studied coal blends. The increase in vitrinite content in the original coals resulted in limiting the disadvantageous effect of semifusinite. The catalytic index (ash compn.) had a substantial effect on the coke reactivity index.