Tamura Koichi, throughout his long career, demonstrated a mastery of wheel throwing, glazing and firing techniques. Since childhood, he showed a talent for drawing and assisted his father, a third generation doll maker. It was a seminal visit to the mingei (folk art) potters Hamada Shoji and Sakuma Totaro in nearby Mashiko that drew him to the field of ceramics.
Initially his works showed the influence of Hamada, but quickly he became known for iron-glazed works that featured reddish-brown, persimmon glazed wax-resist designs against a black ground. A further innovation was his application of brushed white hakeme glaze beneath his iron-oxide patterning. Later on, he further augmented these designs with copper red and lastly experimented with a celadon green glaze ground. His work is characterized by strong brushwork and lyrical, asymmetrical designs. He was designated in 1986 as the Living National Treasure for tetsu-e techniques (iron-glazed patterned ceramics).