Styrene-butadiene-styrene copolymer (SBS) has been used for bitumen modification for years. Different varieties of SBS are produced, e.g. linear and radial. Each type of SBS modifies bitumen in a different way. Knowledge about SBS impact has particular importance in production of waterproofing materials. The article presents the results of laboratory studies of bitumen modified with different SBS quantities, both linear and radial type. Bitumen samples with various SBS content: 3, 6, 9 and 12 %, linear and radial, were subject to testing softening point using Ring and Ball method, penetration P5s/25oC/100g and Fraass breaking point. IR spectrum was also determined for linear and radial SBS. The findings showed that in bitumen with low SBS content (SBS < 3%) the selection of tested modifier is of low importance. However, it is of high importance in production of highly-modified bitumen used for manufacture of waterproofing materials, especially bitumen membranes.