Flexible antennas for GPS reception have been designed and their performance on two different substrates has been evaluated. Two antenna types, a corner-truncated square patch and a planar inverted F-antenna were studied. Antenna patterns were manufactured using conductive pastes and silk screen printing technique. Two different silver pastes and several mixing ratios of silver and carbon pastes were evaluated. It was found that the electrical performance of 25/75% carbon/silver paste mixture does not significantly differ from that of 100% silver paste, whereas the losses of 50/50% mixture are considerably higher. Furthermore, the printing substrate strongly affects the electrical performance of the other studied silver paste.