1SWASP J200503.05-343726.5: A high mass ratio eclipsing binary near the period limit

•The first light curves of V. R and I bands are obtained.•We present new light curve analysis of the short-period eclipsing binary 1SWASP J200503.05-343726.5.•The asymmetrical of the light curves of 1SWASP J200503.05-343726.5 suggest a magnetic activity.•One star-spot model is used to fit the asymmetrical light curves.•The change of orbital period is analyzed in the first time which is increasing.