  We modelled optical light curves of Sco~X-1 obtained by the Kepler space
telescope during K2 mission. Modelling was performed for the case of the strong
heating of the optical star and accretion disc by X-rays. In the considered
model the optical star fully filled its Roche lobe. We investigated the inverse
problem in wide ranges of values of model parameters and estimated following
parameters of Sco X-1: the mass ratio of components $q=M_x/M_v=3.6$
($3.5-3.8$), where $M_x$ and $M_v$ were masses of the neutron and optical stars
correspondingly, the orbital inclination was $i=30^{\circ}$
($25^{\circ}-34^{\circ}$). In the brackets uncertainties of parameters $q$ and
$i$ were shown, they originated due to uncertainties of characteristics of the
physical model of Sco X-1. The temperature of non-heated optical star was $T_2
= 2500-3050$ K, its radius was $R_2=1.25R_{\odot}=8.7\times 10^{10}$ cm, and
its bolometric luminosity was $L_{bol}=(2.1-4.6)\times 10^{32}$ erg s$^{-1}$.
The mass of the star was $M_v\simeq 0.4M_{\odot}$. The contribution of the
X-ray heated accretion disc dominated in the total optical emission of Sco~X-1.
The transition between low and high states occurred due to the increase of
X-ray luminosity by a factor $2-3$.
