Vaanavaraayan (Rajinikanth) is a feudal chieftain, adored and respected by the people of his village. He lives with his grandparents (M. N. Nambiar & Manorama). Following his advice, they abstain from voting in the elections and instead, pool the money given by the candidates to get themselves some basic amenities. Vallavaraayan (Napoleon) is his arch enemy. Their enmity is further sharpened when Vaanavaraayan wins the hand of Vaitheeswari (Meena), whom Vallavaraayan had also wished to wed. Vallavaraayan then convinces the priest of the village temple to mix poison in the holy water that Vaitheeswari drinks. As a result, she becomes incapable of conceiving a baby. But surprisingly, Vaitheeswari soon becomes pregnant-though she has pretended with the help of the mid-wife (S. N. Lakshmi), to do so to uphold her husband's honour. She takes poison and kills herself unable to bear the grief of being incapable of giving her husband a child and on her deathbed makes Vaanavarayan swear to take Ponni (Aishwariya) as his wife. Vaanavarayan however refuses until Ponni agrees to marry Sembattai (Thalapathi Dinesh)- Vallavarayan's hechman-who abandons her to Vallavarayan's vice. Infuriated, Vaanavarayan attacks Vallavarayan and spares his life after giving him a sermon on how to win the heart of the people.

• Rajinikanth as Kanthavelu Vaanavarayan, fondly referred as Yejamaan by the village people.
• Meena as Vaitheeswari, Vaanavarayan's first wife
• Aishwarya as Ponni
• Napoleon as Vallavarayan
• M. N. Nambiar as Vaanavarayan's grandfather
• Manorama as Akhilandeswari, Vaanavarayan's grandmother
• Goundamani as Vellaiyangiri, a worker in Vaanavarayan's house
• Senthil as Azhagiri, Vellaiyangiri's half-brother and rival, a worker in Vaitheeswari's house
• Vijayakumar as Vaitheeswari's father
• S. N. Lakshmi as an old lady who acts as a village nurse
• Rajesh Babu as Vallavarayan's younger brother
• Sandhya as Vallavarayan's wife
• M. Varalakshmi as Vaitheeswari's mother
• Thalapathi Dinesh as Sembattai

After the success of Chinna Gounder, Udayakumar was approached by various producers but he was unsure as to who should play the part of the hero for his next film. Subsequently, he decided to cast Rajini as the hero for his next film. Rajini agreed to act under the direction of Udayakumar. The director expressed his interest to make this film for AVM Productions. Initially, a different script titled "Jilla Collector" was narrated but Udaykumar subsequently opted to film a different script altogether, since AVM Saravanan had felt that the original script might go over budget. The actress Meena was selected as the heroine. Rajini was initially reluctant to have her as the heroine because she had appeared as a child artist for his film Anbulla Rajinikanth and he felt that his fans might not readily accept this pairing. But he eventually agreed to have Meena play the part. "Ejamaan" was Rajini's 141st film and his 8th collaboration with AVM Productions.

Chinna Gounder and Ejamaan had started the trend of portrayals of village chieftain in films. The success of the films inspired similar themes - including Nattamai (1994),^[6] Marumalarchi (1998).

Director Rajmohan directed a film titled Vanavarayan Vallavarayan (2014) named after Rajinikanth and Napoleon's characters, and starring Kreshna and Makapa Anand in lead roles.^[7] Dhanapal Padmanabhan who directed Krishnaveni Panjaalai (2012), rates "Ejaman" as the film that best captured the village flavour and beauty of Pollachi".^[8] One of the songs has inspired as a title for the film - Nilave Mugam Kaattu (1999).

All Music composed by Ilayaraja while lyrics written by Vaali and R. V. Udayakumar. There are a total of eight tracks for this film. The song "Oru Naalum" is based on Sindhubhairavi Raga.^[9]