As the broadband transmission and data compression are being advanced in digital technology at the same time, these enable multimedia easily to exchange and interconnect with each other. The phenomenon to present is generally called ¡§Digital Convergence¡¨. In order to cater to the customers who demand whenever and wherever possible, ubiquitously access to converging services and networks as well, the broadband wireline and wireless access technologies have made significant progress to support and to further ICT (information and communications technology) industry to invest the research and development on the relevant technology, pruducts and services. The development trend of converging in the face of industries, services and networks, FNOs(fixed network operators), who are facing the fixed to mobile substitution(FMS), attempt with the seamless communications proposition to resolve the discontinuous problems caused when or where the user¡¦s handset roams across heterogeneous networks or switches between the fixed and mobile network, so as to motivate user demand for data and multimedia services as well as to restrain the decline of revenue from circuit-switched voice service; On the other hand, MNOs(mobile network operators) are also facing the market saturation on basic voice service gradually, in order to sustain the revenue growth, dual-mode mobile handsets enable the users access to fixed wireless network that substitutes for expensive indoor radio access to mobile network, and make differentiation from competitors to stimulate user demand for value-added services so as to raise ARPU(average revenue per user). Therefore, the business model for FMC(fixed-mobile convergence), is an innovative option to surmount the dilemma of business growth of telecommunications service operators. No matter FNOs, MNOs or SBOs(service-based operators) begin integration among the horizontally layered access networks, e.g. wireless LAN, WiMAX, broadband wireless, 3G, 3.5G and 4G, and change the existing business model varied with the shifting industrial value chain as well in face of emerging convergence and advancing wireless communications technology. The study gives the result with conclusions: 1.The introduction of FMC business is the most advantageous to full-licensed operators or telecom groups; Secondly FNOs can fight against FMS threat to restrain the revenue declined and to gain the revenue stream from MVNO services. 2.Telecom operators who provide with FMC offerings can strengthen competitive advantages with differentiation in the telecom services market to increase revenue and profitability. 3.Telecom operators offer FMC products and services, which help improvement in ARPU of existing customers and acquisition of new ones. 4.FMC offering can increase stickiness on customer retention besides lowering customer churn rate. 5.No matter incumbent or potential new entrant operators who introduce FMC service offering to market, they should take advantages of resources and competence in themselves to address their customer value proposition and positioning, and to adjust the business model to rival with advantageous competitive strategy. Besides, they should consider the timing for the investment on convergence of heterogeneous network varied with industrial environment and regulation so as to raise ROCE. 6.FMC business model is a set of architectural framework, not merely products or services portfolios, applications and selling. The operators must pay close attention to the shift of the external environment and business operation conditions, change the existing business model and strategy so as to keep the business growth and sustained development for lasting enterprises. The study finally suggests: Telecom operators, potential new entrants and the Government in Taiwan should pay close attention to the spectrum licensed for the new technology WiMAX and digital convergence which may come into being ¡§horizontally layered integration¡¨ or ¡§operation beyond the regulated business scope¡¨. The demarcation of regulation the Government takes effect can give consideration to the economic efficiency of market liberalization with fair competition. Asymmetric regulation and deregulation make sure not in implementing ¡§by waiting to become¡¨, and make distribution with choice for the radio frequency spectrum which benefits industry's development as well as adopt explicitly gradual deregulation on the policy and supplementary measure so as to can give consideration to the regulatory function, build the fair market environment and sound telecommunications industry in parallel to further the development in economy.