Imamzadeh Saleh is one of many Imamzadeh mosques in Iran. The mosque entombs the remains of Saleh, a son of Twelver Shi'a Imam. The reputable and holy mausoleum of Imamzadeh Saleh, which is located in bazaar of Tajrish, consist of a courtyard, several family tomb chambers, an ivan, a portico, a mosque, a sepulcher, a tomb and cupola. The present mausoleum dates from the Qajar dynasty. The present structure of Imamzadeh Saleh counts among the outstanding monuments of the Qajar period and the 13th century A.H (14th century A.D) as regards the proportionate interior arches of sanctuary and the constructional style.
However, an old plane-tree, planted in the courtyard, and numerous old tombstones remaining inside the sanctuary (Haram) and in the courtyard, bear evidence that period to the construction of the present building, there had existed the main structure of (Astaneh) which must have belonging to the 7th and 8th centuries A.H (13th and 14th centuries A.D), and which has gradually turned into its present state in consequence of frequent repairs and alterations.
Above the door of the portico which leads into sanctuary, there can be seen some sentences and words in plaster relief and in azure Nasta'liq script on a white background giving the names of Fath Ali Shah and prince Hulaku Khan. The interior of the Haram is decorated with beautiful paintings belonging to the Qajar period.
This mausoleum possesses two sepulchers, the bigger one, the eastern northern and western sides of which are covered with silver-lattice tomb-cage and the southern side with a wooden lattice cage, is remarkable as regards its silver works. The other sepulcher is wooden and possesses square panels. The founder of the silver-plated sepulcher is known as the late Mirza Sa'di Khan, a foreign minister of the Qajar period. Above the northern portal of the courtyard the following two distiches in praise of the Imamzadeh carved in white Nasta'liq script on a background of azure enameled tiles can be seen.