We present the results of optical spectral and photometric observations of the nucleus of Markarian 6 made with the 2.6-m Shajn telescope at the Crimean Astrophysical Observatory. The continuum and emission Balmer-line intensities varied by more than a factor of two during 1992-2008. The lag between the continuum and H{beta} emission-line flux variations is 21.1+/-1.9days. For the H{alpha} line the lag is about 27-days, but its uncertainty is much larger.