We report a discovery of the Zeeman resolved spectral lines , corresponding to the extremely large magnetic field modulus \langle B _ { s } \rangle = 17.5 kG , in the cool Ap star HD 178892 .
The mean longitudinal field of this star reaches 7.5 kG , and its rotational modulation implies the strength of the dipolar magnetic component B _ { p } \geq 23 kG .
We have revised rotation period of the star using the All Sky Automated Survey photometry and determined P = 8.2478 d. Rotation phases of the magnetic and photometric maxima of the star coincide with each other .
We obtained Geneva photometric observation of HD 178892 and estimated T _ { eff } = 7700 \pm 250 K using photometry and the hydrogen Balmer lines .
Preliminary abundance analysis reveals abundance pattern typical of rapidly oscillating Ap stars .