This paper covers the analysis of structure and acoustic features of structural units of mirthful and polite laughter. The research material consists of 100 samples of non-overlapping spontaneous laughter. The analysis revealed that the greatest difference between mirthful and polite laughter can be seen in the structure: polite laughter consists of one, whereas mirthful laughter – of one and more bouts. Some of the differences can be seen in the duration of the same structure laughter units and in the diapason of mean F0, F1, F2, shimmer, and jitter: the duration is longer and the diapason of other acoustic features of mirthful laughter is almost always wider than polite laughter.