The NetBSD/sparc64 port began with NetBSD-current sources from around the NetBSD 1.2 release. Taking NetBSD/sparc as a baseline, Eduardo Horvath modified, added or rewrote all that was necessary. NetBSD/sparc64 had its first formal release with NetBSD 1.5.

The original binary and source snapshot of NetBSD/sparc64 was made available to the public on January 15, 1999. It supported only the Ultra1 family of workstations, with partial support for the Ultra2 family. The onboard SCSI and Ethernet were not supported for the Ultra2, though Sbus SCSI cards were supported.

In early 2000, Paul Kranenburg committed support for the Happy Meal Ethernet, providing onboard ethernet for the Ultra2.

In mid 2000, Matthew Green, with much help from Eduardo Horvath, committed support for the UltraSPARC IIi-based PCI-based systems (Ultra5, Ultra10, AXi, etc.) Some onboard devices (serial, keyboard and mouse) were not supported until later. Shortly afterwards Paul Kranenburg committed the final support needed for the high-end UltraSPARC PCI-based systems, currently only tested on an Enterprise 250 system. Many more significant bug fixes appeared in the following months.

In October 2000, Eduardo Horvath solved the long-standing problem with Sbus ethernet, allowing Ultra1 and Ultra2 class systems to have usable ethernet.

2001 saw further code sharing with the SPARC port, plus many new devices and systems supported, including the SunBlade 100, and many (smaller) UltraSPARC server machines.

The switch to an in-tree toolchain and lots of small improvements in various areas made the sparc64 port a full-grown port as of the NetBSD 1.6 release.

In 2005 the sparc64 port switched over to the generic wscons console framework. Michael Lorenz did most of the work, with support from John Heasley and Martin Husemann. The XFree86 X server was added and replaced Xsun as the default. This brought accelerated consoles and X support for the most common hardware configurations and finally made the sparc64 port usable for desktops.