The aim of this diploma thesis is to closely investigate and describe selected phonetic properties of Czech oral plosives [p t ť k b d ď g] in normal speech. The re- search focuses mostly on temporal characteristics in various contexts; moreover, we deal with the possible manners of plosive articulation in Czech, including non-canonical realizations. Another important part of the present study is a comparison with earlier studies. In the domain of temporal characteristics we examine the influence of various contexts on phone duration. The contexts include: phonetic context, speaker gender, the position of the plosive in the stress unit or articulation rate. We also examine a possible connection between the duration of the plosive and its realization. In the part that deals with the manner of articulation we focus on the individual phonetic properties, for which we investigate especially the conditions and degree of their stability. Furthermore we describe the specific plosive articulations in certain pho- netic contexts and some alternative realizations of certain plosives. The speech material used is mostly spontaneous. All the speakers are non- professionals from various TV broadcasts. Keywords: plosives, duration, phone segmentation, phonetic properties, pho- netic context, gender, articulation..