Variable stars in the globular cluster NGC 4590 (M68)

•Time series photometric studies have been conducted to investigate variable stars.•Periods and Blazhko effects for the known variables have been discussed.•Nine new variable stars have been discovered, 5 of which are RRc type stars.

We present results of time series photometry to search for variable stars in the field of metal-poor globular cluster NGC 4590 (M68). Periods have been revised for 40 known variables and no significant changes were found. A considerable change in Blazhko effect for V25 has been detected. Among nine newly discovered variable candidates, 5 stars are of RRc Bailey type variables while 4 stars are unclassified. The variable stars V10, V21, V50 and V51 are found to be cluster members based on the radial velocity data taken from literature.