Don Smith grew up in Regina and played junior hockey for the Humboldt Indians of the SJHL for two years in the late 1940s. In the fall of 1947, Smith played for the Medicine Hat Tigers of the AJHL for two seasons where he was known as a solid two-way player.
Smith appeared in the only eleven games of his NHL career in 1949-50, when he skated for the New York Rangers, scoring one goal and one assist.
Although Smith never again played in the NHL, he continued to play competitive hockey for another 18 years with an assortment of teams including the Cincinnati Mohawks and the Yorkton Terriers. He retired at the age of 39 after playing the 1967-68 season with the Saskatoon Quakers.
Smith's older brother Ken also played in the NHL with the Boston Bruins.