The 41-year-old, who started his illustrious career with a hit spell on loan at Stenhousemuir has worked with Rennie before at Vancouver Whitecaps in the MLS at the latter end of his playing career.
Miller played under Rennie’s stewardship for two years, with the former Scotland forward making over 40 appearances at the Canadian side.
Both led training this morning ahead of their first match in charge of the Bairns.
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A club spokesperson said: "Kenny joins until the end of the season and brings a wealth of football experience to the Club.
"As a player Kenny had an outstanding career, scoring over 200 goals in almost 700 appearances for a total of twelve different clubs. He was also capped 69 times for Scotland, scoring 18 goals for the international team over a thirteen-year period.
"In 2020 Kenny took a coaching role with Australian club Newcastle Jets, followed by a spell as assistant coach at Western Sydney Wanderers. Kenny will now assist our new Head Coach, Martin Rennie, under whom he played at Vancouver Whitecaps FC."