He was born on 12 th Rabi ' al- Awwal 128 AH/746 AD. The period of his Imaamat is 45 years. He died on 11 th Shawwal 193 AH/27th July 809 AD in the region of Farghana.
He spent his early childhood under the protection of his grandfather Imam Ja'far as-Sadiq (as). He stayed in Medina for most of the time under disguise. Only the selected missionaries (da'is) and few loyal and faithful members knew about his identity. Abbasid caliph Haroon Rasheed was in constant search of him and he had deployed his detectives throughout the city of Medina. The wife of Haroon Rasheed, Zubaida, was loyal and devoted to the rank and status of Imamat of Mohammad ibn Isma'il just like the wife of Fir'aun (Pharaoh) who was faithful and a believer of Moosa (Moses). Zubaida gave all the information to Mohammad ibn Isma'il about the evil plans of Haroon Rasheed. It was because of her assistance and help that Imam Mohammad ibn Isma'il remained alert and migrated to the city of Koofa with his brother 'Ali. He stayed there for long time under disguise.
His father Imam Isma'il (as) died during the lifetime of Imam Ja'far as-Sadiq (as). He was succeeded by his son Wafi Ahmad, who became the 8th Ismaili Imam. The 8th, 9th and 10th Ismaili Imams are believed to have went into seclusion because of the constant threat of life from the Abbasid dynasty.