Abstract: Unifying application log messages using runtime instrumentation includes capturing raw data associated as a log message from an application using an application monitoring module, determining if the raw data is to be filtered based on a filtering configuration, and constructing a log message based on the raw data. A system for unifying application log messages using runtime instrumentation includes a capture engine to capture raw data associated as a log message from an application using an application monitoring module, a determination engine to determine if the raw data is to be filtered based on a filtering configuration, a construction engine to construct a log message based on the raw data, and a log framework monitor engine to monitor an application program interface that invokes a writing action of the log message using at least one log framework to capture the log message in real time.