Self-similar photonic crystals are photnic crystals, for which smaller regions of their unit cells are partially or fully similar to the unit cell itself. Photonic crystals are materials, which have a periodic refractive index, and as a consequence their band structure exhibits photonic bandgaps. In this master's thesis we present five families of self-similar photonic crystals. First we examine a family of one-dimensional self-similar photonic crystals, with two structural parameters. In the band structure of this photonic crystals there are groups of bandgaps, position of which changes linearly with the value of one structural parameter, whereas the other structural parameter has a direct effect on their width. We continue with a two-dimensional family of self-similar photonic crystals, where we are able to fine tune the width and the postion of a specific band gap with both structural parameters. We conclude with the results on three self-similar two-dimenisonal photonic crystal families, which are composed of concetric rings, and square and triangular coloumns. For all three families we show that the postions of the bandgaps can be stongly changed via a single structural parameter. This master's thesis is a contribution to the research of soft photonics and tuneable photonic crystals.