1. An apparatus for controlling execution of mashup WoT service, comprising: a Web of things (WoT) mashup service functionality entity configured to execute a mashup WoT service for a WoT service user; a WoT service execution functional entity configured to execute simple WoT services in order to execute the mashup WoT service of the WoT mashup service functionality entity; and a WoT service repository configured to store WoT service execution descriptions describing execution logic for each of the simple WoT services, wherein the WoT mashup service functionality entity executes the mashup WoT service in accordance with the WoT service execution descriptions read from the WoT service repository.