We present broad-band V and I imaging and long-slit spectroscopy in the optical range \lambda \lambda 3600 – 7500Å of the dwarf irregular galaxy HS 1442+4250 .
The oxygen abundance 12 + log ( O/H ) = 7.63 \pm 0.02 ( Z = Z _ { \odot } /19 ) 12 + log ( O/H ) _ { \odot } = 8.92 ( Anders & Grevesse [ ] ) . 
in the brightest H ii region of HS 1442+4250 places the galaxy among the most metal-deficient emission-line galaxies .
The low metallicity and blue colour ( V – I ) \sim 0.4 mag of the low-surface-brightness ( LSB ) component make HS 1442+4250 a likely rare young dwarf galaxy candidate .
We use four methods to estimate the stellar population age in the LSB component of HS 1442+4250 .
Different star formation histories are considered .
The equivalent widths of hydrogen H \alpha and H \beta emission lines , and of hydrogen H \gamma and H \delta absorption lines , the spectral energy distribution and the observed ( V - I ) colours of the LSB regions are reproduced quite well by models with only young and intermediate-age stellar populations .
By contrast , the observational data can not be reproduced by a stellar population formed continuously with a constant star formation rate in the age range from 0 to \ga 2 Gyr .
While a faint old stellar population in HS 1442+4250 with an age \ga 2 Gyr is not excluded , we find no evidence for such a population from the present data .