Wollo is a line of Windows VST plug-ins developed by Norwegian ambient and electronic musician Erik Wøllo, released as donationware through his own site. The instruments are designed around the textures and atmospheres common to Wøllo's own work in ambient, drone, and space music, and reflect what he describes as tools "made for my needs" and his particular musical style.

The catalog includes the Wollo Voyager and Wollo Drone analog-style synthesizers, Wollo FMERA — an FM synth paired with a wave player and a built-in stereo female voice sample — Wollo Beat, a drum and percussion module that combines Roland-style electronic sounds with sampled acoustic kits, and Wollo Spacer, a multi-effects plug-in. The plug-ins are produced out of Wøllo's Wintergarden Studio under his Monumental Records imprint, and have been distributed through outlets like KVR Audio and Plugin Boutique alongside the developer's own site.

Erik Wollo has 3 products cataloged on Equipboard, including Synth Plugins and Reverb Plugins.