Objective: To emphasize the importance of an early diagnosis and an adequate treatment in conjunctival tumors. Methods: We present two clinical cases and compare the course of each case: one of conjunctival intraepithelial neoplasia (CIN) which took a positive course, and a fatal case of squamous cell carcinoma (SCC) with intraocular and orbital extension. Results: Epithelial conjunctival malignancies are one of the most prevalent ocular surface tumors. Among these, CIN are the most common. CIN have an excellent prognosis, given adequate treatment. However, when the diagnosis of CIN is late, the epithelial basement membrane will be affected, resulting in SCC. SCC may have poorer results due to its capacity to infiltrate near tissues and create distant metastasis. Conclusion: It is not common today to treat patients with orbital extension of SCC; however, it is crucial to note the importance of an early diagnosis of conjunctival malignancies. An early diagnosis is essential to prevent the transformation to other life-threatening types.