Mittelsinn is a municipality in the Main-Spessart district in the Regierungsbezirk of Lower Franconia (Unterfranken) in Bavaria, Germany and a member of the Verwaltungsgemeinschaft (Administrative Community) of Burgsinn.

This was destroyed on Kristallnacht (9 November 1938), as recalled by a memorial plaque at the savings and loan institution across the street from the synagogue's former site.

On the escutcheon’s upper half, on the dexter (armsbearer’s right, viewer’s left) side, are the arms formerly borne by the Prince-Bishopric (Hochstift) of Würzburg, referring to the community’s former allegiance to that state.

On the sinister (armsbearer’s left, viewer’s right) side, the two staves refer to the special tithe court whose seat Mittelsinn once was.

The charges in the escutcheon's lower half, a waterwheel and a wavy pale (vertical stripe) symbolize the River Sinn and its mills.