Johannes (Johan) Andreas Mühlensteth (7 April 1746 - 11 January 1819) was a Danish pharmacist.
He purchased Svane Apotek in Copenhagen in 1781 and was in the same time granted permission to move it from its old building in Højbrostræde to Østergade.
He lectured on chemistry at the University of Copenhagen in 1783 and acted as assessor pharmaciae in the Collegium medicum until 1803.
[1] Mühlensteth married Maria Christina Bruun (1 August 1754 – 5 April 1829) on 15 May 1782 in Church of Our Lady.
In 1783 he received media attention for sending up the first Danish hot air balloon.