The invention provides a method and device for implementing an OTDOA in an indoor communication system. According to one embodiment of the invention, the method comprises a step of determining main RRH groups for each user equipment, wherein the main RRH groups comprise a service RRH and at least two auxiliary RRHs, and the service RRH and at least two auxiliary RRHs are used for implementing the positioning point of the OTDOA for user equipment, a step of determining multiple isolated RRH sets, wherein the RRHs in each isolated RRH sets are from different main RRH groups, and a step of distrubuting a corresponding resource mapping pattern for the multiple isolated RRH sets, wherein the resource mapping pattern is used for indicating a resource of transmitting a positioning reference signal. Through the invention, the user equipment can distinguish RRHs which share a same cell ID, the introduction of a high overhead is not needed, and the user equipment can maintain a backward compatibility with traditional UE and is compatible with an existing protocol.