  We present optical lightcurves of 428 periodic variable stars coincident with
ROSAT X-ray sources, detected using the first run of the SuperWASP photometric
survey. Only 68 of these were previously recognised as periodic variables. A
further 30 of these objects are previously known pre-main sequence stars, for
which we detect a modulation period for the first time. Amongst the newly
identified periodic variables, many appear to be close eclipsing binaries,
their X-ray emission is presumably the result of RS CVn type behaviour. Others
are probably BY Dra stars, pre-main sequence stars and other rapid rotators
displaying enhanced coronal activity. A number of previously catalogued
pulsating variables (RR Lyr stars and Cepheids) coincident with X-ray sources
are also seen, but we show that these are likely to be misclassifications. We
identify four objects which are probable low mass eclipsing binary stars, based
on their very red colour and light curve morphology.
