William Herschel discovered NGC 6342 = H I-149 on 28 May 1786 (sweep 569) and recorded "cB, lE, pS, easily resolvable." His position is at the northwest edge of the globular.

Pietro Baracchi observed the GC on 3 Sep 1885 with the Melboure telescope and showed a separate small clump or knot on the NE side.

400/500mm - 17.5" (7/27/92): moderately bright, fairly small, 2' diameter with an irregular outline, increases to fairly well-defined bright core, mottled. A mag 12 is just off the south tip and a very faint extension or lane extends towards this star. One or two very faint stars mag 14.5-15 are at the NE edge. A less well-defined extension to the SW includes one or two threshold stars. The cluster has a lively appearance but there was no additional resolution.

Notes by Steve Gottlieb