We have collected pulsar flux density observations and compiled spectra of 281 objects .
The database of Lorimer et al .
( [ 1995 ] ) has been extended to frequencies higher than 1.4 GHz and lower than 300 MHz .
Our results show that above 100 MHz the spectra of the majority of pulsars can be described by a simple power law with average value of spectral index < \alpha > = -1.8 \pm 0.2 .
A rigorous analysis of spectral fitting revealed only about 5 % of spectra which can be modelled by the two power law .
Thus , it seems that single power law is a rule and the two power law spectrum is a rather rare exception , of an unknown origin , to this rule .
We have recognized a small number of pulsars with almost flat spectrum ( \alpha \geq - 1.0 ) in the wide frequency range ( from 300 MHz to 20 GHz ) as well as few pulsars with a turn-over at unusually high frequency ( \sim 1 GHz ) .