One of the biggest issues in the current Korean broadcasting industry is digital transition. Terrestrial broadcasters currently send both digital and analog signals to the public. But the government plans to switch off the analog signals and send only the digital ones in a few years. However, the penetration rate of the digital TVs or the digital set-top boxes are very low in Korea, hindering digital transition. So the government and the terrestrial broadcasters takes the introduction of multichannel services to the terrestrial broadcasting into serious consideration. By using a theoretical model, we examine the effects of the multichannel services on the platform competition between the terrestrial broadcasting and the cable TV services, the digital TV sales, and the social welfare.