In 1950 -1970 Leonid Tkachenko travelled by the virgin lands of Kazakhstan, building of Sayano-Shushenskaya Dam by ancient Russian towns Pskov, Veliky Novgorod, Vladimir, Suzdal and also in Siberia, Middle Asia and Zakarpatye.
In the 1960s in art of Leonid Tkachenko took place a gradual changes from academic style and plain air painting to the symbolic compositions and more plastic expression.
There were a growing abstract role of colour and rhythm with subsequent release into the space of philosophical tasks of conceptual art in his work.
Winter Evening", "The Airplane has Flew" (all 1955), "The Year 1917" (1957), "May-Day at Vasilievsky Island" (1958), "Call of Hiroshima" (1960), "Leningrad" (1961), "A Fine Day" (1962), "A Portrait of G. Egoshin, Z. Arshakuni, Y. Krestovsky" (1968), "Shah-i-Zinda.
Bukhara", "A Vase" (1974), "Surgeon Amosov" (1975), "A Fantasy on the Reminiscence about Dante and Michelangelo", "Mayakovsky" (1976), "Golden Cactuses", "Apples in a Golden Vase" (both 1977), "A Concert for the Piano", "A Concert with the Ballerina" (both 1978), "L. Tolstoy" (1979), "Music for the World", "Wild Flowers" (both 1980), "Still life with Two Cactuses", "Still life with Snowdrops" (both 1981), "Alexander Block.