The organic sulfur functionalities in the pyridine extracts obtained from lignite (lignite A), subbituminous coal (subA), and bituminous coal (mvb) were studied by atmospheric pressure-temperature-programmed reduction (AP-TPR) method. The extraction yield was in the range of 6.7-29.3 wt % with a maximum for medium volatile bituminous coal. The H2S AP-TPR recovery for the pyridine extracts was relatively low, not higher than 45%. The coupling of the AP-TPR reactor with a different detection system from potentiometric one, i.e., with a mass spectrometer, enables the detection not only of H2S but also of other sulfur-containing compounds, which were released in the volatile products during reductive pyrolysis. Alkanethiols, thiophene, and its C-1-C-2 alkylated derivatives were detected in the volatiles. Both the char and the tar produced during an AP-TPR experiment were also studied by atmospheric pressure-temperature-programmed oxidation (AP-TPO) to monitor the sulfur compounds left and captured in the AP-TPR solid and liquid residues, respectively. The obtained extracts were characterized by high sulfur content, 1.18-3.74 wt %. The organic sulfur functionalities distribution of the pyridine extract reflects the rank of coal subjected to extraction. The AP-TPR analysis showed that for the extract from lignite thiols, alkyl and alkyl aryl sulfides dominate, whereas for the extract from subbituminous coal a comparable proportion of alkyl and alkyl aryl sulfides and thiophenes is found. Thiophenes are the major organic functionalities in the pyridine extract from bituminous coal.