Armin succeeded his father as head of the House of Lippe following the latter's death on 30 December 1949.
On 22 March 1953, he renounced his position in favour of his older half brother, Prince Leopold.
Ernst August died in 1990 and his son Prince Friedrich Wilhelm of Lippe (b.
He was a first cousin of Prince Bernhard of Lippe-Biesterfeld, consort of Queen Juliana of the Netherlands, and was a child attendant at their 1937 wedding.
Prince Armin married Traute Becker (16 February 1925 – 25 February 2023), daughter of Gustav Becker and Charlotte Meyer, on 27 March 1953, in Göttingen, Germany, in a civil marriage followed by a religious ceremony on 29 March 1953, in Celle, Lower Saxony, Germany.