We presented a low-precision spectrum for HI Leo, Transiting Exoplanet Survey Satellite data for V523 Cas, and  new photometry for both K-type contact binaries. Comparing their light curves on different observing dates, we  found small intrinsic variabilities, such as variable amplitudes for HI Leo and the varying heights around the  second maxima for V523Cas. By the Wilson–Devinney Code, we deduced six photometric solutions. The dark  spot of V523Cas may appear on the surface of the more massive component on BJD2458768, while it disappears  on BJD2458779. Our results indicate that the two binaries are W-type shallow-contact binaries (f 10%). From  the eclipse timing residuals, we found that the orbital periods may continuously increase, accompanied by one to  two light-time effects due to additional bodies. The modulated periods and semi-amplitudes are P3 = 25.8(±1.0) yr  and A3=0.^d0066(6) for HILeo, P3=114.8(±2.0)yr and A3=0.^d0448(12), P4=18.89(±0.14)yr and A4 =0.^d0025(2) for V523Cas, respectively. The orbital period secularly increases at a rate of dP/dt=2.86 (±0.11) ×10⁻⁷day yr⁻¹ for HILeo and dP/dt=3.45(±0.07)×10⁻⁸day yr⁻¹ for V523Cas, which may be attributed to mass transfer from the secondary to the primary. With mass transferring, the shallow-contact binaries, HILeo and V523Cas, will evolve into the broken-contact configurations.

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