A system and a method of interface communication being compatible with SFP+ optical modules and QSFP+ switch are provided. The system includes an adapter card. The adapter card includes a set of SFP+ golden fingers that comply with the SFP+ protocol, a set of QSFP+ golden fingers that comply with the QSFP+ protocol, and a microcontroller unit. The adapter card communicates with the SFP optical module through the SFP+ golden fingers, and communicates with the QSFP switch through the QSFP+ golden fingers. The microcontroller unit is used to extend and process the pin information in the adapter card, and to convert the two different protocols of SFP+ and QSFP+, so that the module under the SFP+ protocol can respond under the port of QSFP+, so as to realize the data communication between the SFP+ optical module and the QSFP+ switch.