Hinduism is the second-largest religion in Sindh, numbering 4.17 million people and comprising 8.73 percent of the province's population in the 2017 Pakistani census. Sindh has the largest population and the highest percentage of Hindus in Pakistan. Sindh has the Shri Ramapir Temple, whose annual festival is the country's second-largest Hindu festival (after the Hinglaj Yatra).
 The region and its rulers play an important role in the Hindu epic, Mahabharata. Hinduism and Buddhism were the predominant religions in Sindh before the arrival of Islam, when a number of Hindu castes and communities occupied the region. Many ancient Hindu temples still exist; many Hindu dynasties, including the Gupta, Pala, Kushan and Hindu Shahis, ruled the region before Muhammad ibn Qasim led the Umayyad army in the Islamic conquest of Sindh. The region still had a Hindu majority, but repeated campaigns and persecution by the Delhi Sultanate led to a gradual decrease in the Hindu population and an increased number of Muslims. Hindus were a minority in the region at the time of the Mughal Empire. After the formation of Pakistan, most Hindus migrated to India.
 In the 2017 census, Sindh's 4.18 million Hindus were 8.73 percent of the province's population; this included 83,000 (1.74 percent) scheduled-caste Hindus. However, the proportion of scheduled caste Hindus is actually higher as they categorize themselves as Hindus in the census rather than as Scheduled Caste Hindu. According to the Election Commission of Pakistan, voters who said that they were Hindu were 49 percent of the total in Umerkot and 46 percent in Tharparkar. According to voter estimates, Hindus have a population of 50,000 or more in 11 districts. All are in Sindh, except for Punjab's Rahim Yar Khan District.
 Umerkot District (52.15 percent), in Sindh, is Pakistan's only Hindu-majority district. The province's Tharparkar District has the highest district Hindu population. Four Sindh districts (Umerkot, Tharparkar, Mirpurkhas and Sanghar) account for more than half of the country's Hindu population.
 Many Hindus – especially in Sindh's rural areas – follow the teachings of 14th-century Ramdevji, whose main temple (Shri Ramdev Pir temple) is in Tando Allahyar. A growing number of urban Hindu youth in Pakistan associate themselves with ISKCON. Other communities worship mother goddesses, their clan (or family) patrons. Many Hindus in Sindh revere Guru Nanak, the founder of Sikhism, along with the Hindu gods. A large percentage of Sindhi Hindus consider themselves Nanakpanthi.
 Sindhi Hindus who cannot afford travel to India to release their loved ones' remains into the Ganges go to Churrio Jabal Durga Mata Temple in Nagarparkar. According to a study, most scheduled-caste Hindus (91.5 percent) in the province's Tharparkar and Umerkot Districts faced discrimination and believed that its political parties are ignoring them. Forced conversion of Hindu girls is a major problem faced by Hindus in Sindh, with an increased number of cases in the southern districts of Tharparkar, Umerkot and Mirpur Khas. Sindh is Pakistan's only province with a separate law governing Hindu marriages.
 Ten seats are reserved for minorities in the provincial assembly. In 2018, the Sindhi Krishna Kumari Kohli was the first Hindu to win a women's reserved seat in the Senate. In the 2018 general election, Mahesh Kumar Malani (representing Tharparkar-II) was the first Hindu candidate to win a general seat in the National Assembly of Pakistan. In the 2018 provincial assembly election, Hari Ram Kishori Lal and Giyan Chand Essrani were the first non-Muslims to win a general seat (non-reserved) in a provincial-assembly election.