Malini had played small roles in Pandava Vanavasam (1961) and Idhu Sathiyam (1962). In 1968, she was chosen to play the lead opposite Raj Kapoor in Sapno Ka Saudagar and promoted as Dream Girl.”

Malini played the lead in Johnny Mera Naam (1970). Roles in subsequent films like Andaz (1971) and Lal Patthar (1971) established her as a leading actress. In 1972, she played a double role opposite Dharmendra and Sanjeev Kumar in Seeta Aur Geeta. She also received a Filmfare Best Actress Award for the film. The list of successful films she starred include Sanyasi, Dharmatma and Pratigya, Sholay, Trishul to name a few.

Her first film with Dharmendra was Tum Haseen Main Jawaan (1970). The two got married in 1980. Dharmendra was already married at the time and had children, two of whom later became Bollywood actors Sunny Deol and Bobby Deol. Malini and Dharmendra have two children, Esha Deol (born 1981) and Ahana Deol (born 1985).

In the 1990s, she produced and directed the 1992 film Dil Aashna Hai, starring Divya Bharti and Shah Rukh Khan in the leading roles. She also produced and directed her second feature film Mohini (1995), starring her niece Madhoo and actor Sudesh Berry in the leading roles. She then focused on dancing and television work, only occasionally appearing in films. In 1997, she acted in Vinod Khanna’s production Himalay Putra which marked the debut of Vinod’s son Akshaye Khanna.

In 1999, Malini campaigned for the Bharatiya Janata Party (BJP) candidate, Vinod Khanna, a former Bollywood actor, in the Lok Sabha Elections in Gurdaspur, Punjab. In February 2004, Malini officially joined the BJP. From 2003 to 2009, she served as an MP to the upper house – the Rajya Sabha, having been nominated by the then President of India, Dr. A.P.J. Abdul Kalam. In March 2010, Malini was made general secretary of the BJP, and in February 2011, she was recommended by Ananth Kumar, the party general secretary. In the 2014 general elections for the Lok Sabha, Malini defeated the Mathura incumbent, Jayant Chaudhary (RLD) by 3,30,743 votes. Malini was then elected to the Lok Sabha.

Malini was the editor of New Woman and Meri Saheli, Hindi women’s magazine. In 2000, Malini was appointed as the first female chairperson of the National Film Development Corporation for a term of three years.

After taking a break from films for a number of years, Malini made a comeback with Baghban (2003), for which she earned a Filmfare Best Actress Award nomination. She also made guest appearances in the 2004 film Veer-Zaara and the 2007 film Laaga Chunari Mein Daag. In 2010, she acted in Sadiyaan alongside fellow veteran actress Rekha. In 2011, she produced and directed her third feature film Tell Me O Khuda which featured both her husband Dharmendra and her daughter Esha Deol, which was a box office failure. In 2017 she acted in the film Ek Thi Rani Aisi Bhi in the role of Vijaya Raje Scindia of Gwalior, with Vinod Khanna as her husband, unfortunately it was Vinod Khanna’s last film. The film was directed by Gul Bahar Singh. The film was released on 21 April 2017. Her latest film is Shimla Mirchi, starring Rajkummar Rao and Rakul Preet Singh. The movie was theatrically released in India on 3 January 2020. And it was made available on Netflix on 27 January 2020.

Malini studied Kuchipudi with Vempati Chinna Satyam and Mohiniattam with Kalamandalam Guru Gopalakrishnan. She has played a number of dance roles including Narasimha and Rama in Tulasidas’s Ramcharitmanas. In 2007, she performed in Mysuru on the eve of Dussehra, where she played the roles of Sati, Parvati and Durga.

In 2007, Malini entered a promotional contract with Kent RO Systems, makers of a mineral water purifier system. Malini also became a brand ambassador for Pothys, a textile showroom in Chennai.

Malini is a supporter of the animal rights organisation, PETA India. In 2009, she wrote a letter to the Mumbai Municipal Commissioner urging him to ban horse carriages from Mumbai’s busy streets. In 2011, she wrote to the Union Minister for Environment and Forests, Jairam Ramesh, urging him to ban bull fighting (jallikattu). She said, “My friends at PETA have organised investigations at jallikattu events and documented that bulls are pulled roughly by their nose rings, punched, pummelled, hit with sharp sticks and crammed into trucks so tightly that they can barely move”. Malini won the title of “PETA Person of the Year”. As a vegetarian, she said, “Knowing that my food choices are helping the planet and animals too, makes me happy”.

On 11 June 2015, Malini became grandmother when her younger daughter Ahana Deol gave birth to her first child, Darien Vohra. On 20 October 2017, she became grandmother for the second time when elder daughter, Esha Deol Takhtani gave birth to a girl, Radhya Takhtani.