Contact Center is a form of Customer Relationship Management, where customers can interact with a company through its single point of contact and serves mainly as a tool for the company to maintain its service to the customers. Contact center is generally operated by many Agents and can accepts thousands of phone calls every day, depending on the company’s scale and customer base. In order to correctly serve the customers, Agents need to understand many knowledge which the company has, and this is the main reason why Agents need to master the company’s Knowledge Management System (KMS). Inability of Agents to interact with the KMS will be a serious problem for the company. In this paper, we studied the acceptance of Halo Info, a form of KMS in one of the biggest banking contact center in Indonesia, called Halo BCA. We used modified TAM version 2, with a total of 11 variables, 31 indicators, and 12 hypotheses. The research instrument was a 31 items questionnaire. We gathered 283 respondent data, and analyzed it using PLS-SEM. The research findings are: Usage Behaviour (UB) is significantly affected by Intention to Use (IU); IU is proven to be greatly affected by Perceived Ease of Use (PEU), Perceived Usefulness (PU), and Subjective Norm (SN); PEU is significantly affected by System Self-Efficacy (SSE) and Interface Usability (IUSB); PU is significantly affected by Job Relevance (JR) and PEU, but is not significantly affected by Output Quality (OQ), Image (I), Result Demonstrability (RD), and SN.