We present the results of stellar photometry of the polar-ring galaxy NGC~660 using the Hubble Space Telescope ’ s archival data obtained with the Wide Field Planetary Camera 2 .
The final list of the resolved stars contains 550 objects , a considerable part of which are blue and red supergiants belonging to the polar ring .
The analysis of the Colour Magnitude Diagram for polar ring stars shows that it is best represented by the isochrones with metallicity Z = 0.008 .
The process of star formation in the polar ring was continuous and the age of the youngest detected stars is about 7 Myr .