Micro injection molding techniques are important and may have applications in the computer, communication, consumer and medical industries. Most micro injection molding machines are two-stage reciprocating screw and plunger type mechanism. This type of molding machines use a reciprocating screw to plasticize the plastic and use a plunger to meter and inject. A new designed hot runner type micro injection molding module was designed and fabrication. This module could be installed in most reciprocating screw injection molding machine and has the capability of precise metering for micro injection molding. In this study, a special-purpose controller and a human-machine interface were designed for the micro injection molding module. The performance of this micro injection molding module was tested with a reciprocating injection molding machine. The test results showed that the metering precision of using this module was at least as good as a two-stage reciprocating screw and plunger type micro injection molding machine.