Industrial symbiosis is the exchange of by-products, energy and water between industries, centered on a collective approach, and in order to achieve competitive advantages. It is central to the concept of Eco-Industrial Park (EIP) and requires continuous monitoring of the professionals involved. Performance indicators for the measurement and monitoring of industrial symbiosis have been proposed and identified in the literature, however there is no consolidate indicator that is widely used in practice. These indicators require validation in order to evaluate and choose which options are able to measure the industrial symbiosis. There are two types of indicators validation, the conceptual validation and the empirical validation. This study investigates the integration of the conceptual validation and the empirical validation in the evaluation of the industrial symbiosis indicators. It is proposed the combined use of an indicator validation methodology based on expert judgment, the 3S Methodology, and a simulation technique, the Agent-Based Modeling (ABM). The proposed procedure aims to validate any indicator of industrial symbiosis, providing specific criteria to the evaluation.