The son of a famous architect A. O. Bernardazzi, many built in Odessa and Chisinau. The family had five children, Alexander was the second. He studied at the Higher art school at the Imperial Academy of arts and "for his excellent knowledge in the arts and Sciences" was awarded in 1903 the title of artist-architect. Some time works as a "free artist" — his project to build a number of tenement houses, including in 1910 the famous "House-tale" . In 1911, accepted the post of architect of the Department of education. In 1915-1917 by the project of A. Bernardazzi built "6th St. Petersburg gymnasium named heir Tsesarevich and Grand Duke Alexei Nikolaevich".
He teaches at the Higher women's architectural courses E. F. Bagaeva, Women's Polytechnic courses. A member of the "Society of the Intimate theatre", one of the founders of the literary-artistic cabaret "stray Dog".
In 1916-1917 he participated in the construction of the Perm University and also (together with his brother, E. A. Bernardatsi) was the author of the project of the building of the Mining Institute in Yekaterinburg. In connection with the need to be present at these construction sites, 1 Jul (18 Jun) 1917 departed on a long trip and Petrograd did not return.
It is known that in 1921 A. A. Bernardazzi worked in Harbin , his fate is unknown.