Background: Now-a-days, the forces of globalization derive firms to go to international market. When a firm thinks to expand its business outside of the home market, it needs to explore the form of operation through which it will enter into the foreign market. International entry mode research deals with this matter. (Brouthers et.al.2007). Selection of an optimal entry mode strategy is very important because it is very difficult to change or correct and have a long-term impact on the firm’s foreign operation (Pedersen, Petersen, & Benito, 2002). Actually, it is very difficult for a firm to serve in the market on a permanent basis without a well formulated entry strategy. (Pehrsson A. 2008). Market entry mode strategies are influenced by both firm and country level factors and a firm must take into consideration these factors in choosing an appropriate entry mode. Purpose: The basic purpose is to gain a deep knowledge about the critical factors in selecting an optimal international market entry mode strategy to enter into an emerging market. The minor purpose is to justify the suitability of the target market. Methodology: Due to the dependency on subjective interpretation of text or other visual material and small sample was used to investigate the specific phenomena, qualitative method has been practised in this research process. Secondary data has been mainly collected from e-sources, and primary data has been collected through phone interview with the three foreign mobile telecom companies in Bangladesh. Findings: Bangladesh mobile telecommunication market is still attractive for the foreign entrants and the optimal entry mode strategy is joint venture to enter into the moderately attractive industry. Implications: The study has showed that international entry mode strategy is affected by various organizational, economical, Institutional, and sociological factors (categorized as country and firm level factors). This research has also provided relevant information to the potential foreign firms about which country and firm level factors should consider in formulating a well entry mode strategy in perspective of an emerging market.