Siti Mariam binti Ismail (Jawi: سيتي مريم اسماعيل ; 20 April 1933 – 1 December 2015), better known by her stage name as Mariani was a Malaysian-Singaporean Malay actress, singer and model popular during the 1950s and 1960s. She was the older sister of Biduanda Saloma and sister-in-law of P. Ramlee. Mariani was considered one of the most popular actresses at Jalan Ampas Studios in Singapore, dubbed the "Golden Age of Malay Cinema" at the time. She starred in more than 30 films over her 63-year career span.

Mariam's career began after winning the Singapore Queen Contest in 1951 when she was 17. She was the first lady to ever hold the title. However, she did not represent Singapore at that time. The show has been a stepping stone for her to engage in acting. After that, she was offered an act by Malay Film Productions, but she refused because her ambition was to be a doctor. After two years, it was after being persuaded by Saloma, then Mariani agreed to act. Her first film was Chemburu directed by S. Ramanathan in 1952. After the success of the movie, Mariani was offered another acting in the company's films including Palace of Dreams, A Return, Labu Labi, Nasib Si Labu-Labi and Tiga Abdul. After the closure of Malay Film Productions and the separation of Singapore from Malaysia, she continued her acting career at Studio Merdeka in Kuala Lumpur. She starred in many films in the studio like Sweet Mashed Film and Discouraged.

In her later years, Mariani continued to act and her latest appearance in films was Pontianak Harum Sundal Malam 2 directed by Shuhaimi Baba in 2005. She also starred in various dramas such as Nur Qalesya, Bila Larut Malam and others more. In 2007, she along with her husband, founded a production company, Kus Semangat Sdn. Bhd., which she owned with her husband, until her death in 2015.

On 1 December 2015, Mariani died after battling with colon cancer, at her home in Taman Kosmo Jaya, Sentul, Kuala Lumpur. She was 82 years old. Her body was sent to Al-Hidayah Mosque in Jalan Sentul and was buried in Jalan Ampang Muslim Cemetery, Kuala Lumpur.