The impact of the Covid-19 pandemic on the care of children with cancer in LMIC is of great concern, particularly on diagnosis and abandonment of treatment rates. Data supporting this concern however is limited to survey and anecdotal information. A retrospective with two cohorts design was used to compare new diagnosis and monthly abandonment rate in Java, Indonesia. We found that new diagnoses rates had dropped significantly during Indonesia’s first wave as compared to a pre-pandemic cohort [rate ratio 0.57, 95th (CI) 0.41-0.79)] and that as the first wave progressed, abandonment rates also rose in a statistically significant manner.