Context: The Protease inhibitors in Potato juice have anti-inflammatory effect which are help to reduce the pathological changes of tissue caused by phlebitis in sick children. Aims: The study aims to compare the effectiveness of MgSO4 fomentation vs potato juice application on phlebitis. Setting and Design: Paediatric Medicine ward in Burdwan Medical College and Hospital, Burdwan. Quasi-experimental equivalent time series design was used for the study. Material and Methods: Non –probability purposive sampling was used the sample comprised of 50 sick children 1-3 years of age were getting intravenous medication and develope phlebitis. Pretested reliable tool had introduced. Data were collected through interview schedule, observation and assessment method. Statistical analysis used: Collected data were tabulated, analyzed and statistically calculated by descriptive and inferential statistics .Inferential statistics had used both dependent and independent t test by using ANOVA. Results: In total. Out of 50 children, the incidence of grade II Phlebitis was 40% and grade III Phlebitis was 60%. The mean reduction score was less in experimental group II was treated with potatao juice (.22,0) than experimental group I treated with MgSO4 fomentation (1.3 and 0.04 ) in subsequent 12th, 24th, 36th, 48th and 60th hour with mean difference 1.8 and 0.04, which statistically significant at .05 level with df 48 as seen by t value 2.01. Conclusions: The study result shows that potato juice was better than 50% magnesium sulphate fomentation in reduction of phlebitis in less time and also effective for tissue regeneration. Keywords: Effectiveness; Sick children; Magnesium Sulphate Formentation; Potato juice application; Phlebitis; Pain.