It is the headquarters of Jallah Jeem-Mailsi Tehsil, an administrative subdivision of Vehari District.Sutlej-Jeemi river flows in the East.

Mailsi is located in the Indus Valley near the city of Multan in central Pakistan.

Farming is the primary economic activity in Mailsi and exports include cotton, wheat, sugarcane, rice, and henna.

There are three canals, Mailsi Link, Faddah and Dhamakki, There are many sub-canals and a number of streams for irrigation is also there.

The climate is arid, characterized by hot summers and cool winters, and wide variations between extremes of temperature at given locations.

Mailsi-Jallah Jeem has four seasons: a cool, dry winter from December through February; a hot, dry spring from March through May; the southwest monsoon period, from June through September; and the retreating monsoon period of October and November.

Mailsi is a Tehsil Headquarters of the city of Mailsi-Jallah Jeem and one of the Tehsil/administrative areas of the Vehari district.

The city of Mailsi is also has a Combined Military Hospital.Pakistan Army Medical Corps The first Government Primary School was established in 1864 during British Raj after failed freedom war of 1858.

The first girls’ high school was established in 1890, which later became a middle high school in 1972. in 1949, Islamic Educational Institute Jamia Taleem Ul QUran, Multan Road Mailsi was established by Mufti Muhammad Kaleemullah, Where 1000+ students learned Islamic studies.

On 2 January 1972, the Government of Prime Minister Zulfiqar Ali Bhutto nationalized educational institutions throughout Pakistan.

Among the first few new private educational institutions in Pakistan, was Mailsi Model School on Multan Road.

[citation needed] Mailsi, میلسی, is located on the northern alternate rail and overland route to Bahawalpur and Lahore, the capital of the Punjab province of Pakistan.

The western route connects with Multan and in south-east side Bahawalpur & south-west is Kahror Pakka.

Sardar Pur Jandhir Library also attracts a number of students and researchers across the country to it.