Inhibition of return (IOR) is a robust phenomenon that refers to finding targets faster at novel locations than seen locations. IOR helps in visual search activity as it facilitates searching for new objects on uncued locations.  In the present study effect of cue (valid and invalid cue), task type (Discrimination & detection tasks) and SOA levels (500ms & 750ms) is explored on the IOR phenomenon during sustained attention tasks. Sustained attention is a phenomenon in which attention is required to sustain for longer duration of time. A 2 (Task type: Detection & Discrimination Tasks) × 2 (SOA levels: 500ms & 750ms) × 2 (Cue Validity: Valid & Invalid) × 3 (time period: blocks of 10 min) mixed factorial design with repeated measure on the last two factors has been employed. Correct detection and RT were taken as performance measures.  Results revealed significant effect of cue on correct detection.  Participants detected more targets under valid cue condition than invalid cue condition on both SOA levels. Participants have higher hit rates under valid cue condition on detection task than discrimination task on both SOA levels.  RT results showed that response was facilitated under valid cue than invalid cue condition on both the task types & SOA levels. Thus, the findings showed that IOR was not seen in discrimination as well as detection task on any SOA levels taken. Probably the SOA level was not sufficient to generate the IOR. Other responsible reasons could be small sample size and nature of task for not generating the IOR.