We sought to investigate the association between participating in multiple nutrition assistance programs - including the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), Pandemic Electronic Benefit Transfer (P-EBT), and the Supplemental Nutrition Assistance Program (SNAP) - and child dietary intake frequencies early during the COVID-19 pandemic among WIC-participating children 12-59 months of age. Data from the 2020 Los Angeles County WIC Survey, conducted July-December 2020 among a random sample of WIC-participating families in Los Angeles County, including child diet intake frequencies (servings/day or times/day) as reported by their mothers for sugar sweetened beverages (SSBs), 100 % juice, milk, water, sweets, fruits, and vegetables (outcomes); participation in WIC, P-EBT, and SNAP (exposure); and child, maternal, and household covariates (n = 3563). We fitted covariate-adjusted Poisson regression (for water, milk, fruits, vegetables) or negative binomial regression (for SSBs, sweets). Compared to WIC-participating children in WIC-only households: 1) WIC-participating children in WIC + SNAP (pre-pandemic enrollment) households consumed 100 % juice more frequently (incidence rate ratio [IRR] = 1.12, 95 % confidence interval [CI] = 1.01-1.24); 2) WIC-participating children in WIC + P-EBT households consumed fruits less frequently (IRR = 0.94, 95 % CI = 0.90-0.99); 3) WIC-participating children in WIC + P-EBT + SNAP (during pandemic enrollment) households consumed milk more frequently (IRR = 1.13, 95 % CI = 1.05-1.21); and 4) WIC-participating children in WIC + P-EBT + SNAP (pre-pandemic enrollment) households consumed SSBs (IRR = 1.25, 95 % CI = 1.07-1.47), sweets (IRR = 1.11, 95 % CI=>1.00-1.22), and milk (IRR = 1.08, 95 % CI = 1.02-1.15) more frequently, and water (IRR = 0.94, 95 % CI = 0.89-<1.00) and fruits (IRR = 0.95, 95 % CI = 0.90-0.99) less frequently. Enhanced nutrition education may be needed for WIC-participating children who live in households participating in multiple nutrition assistance programs since they consumed foods discouraged by WIC (SSBs, sweets) more frequently and foods encouraged by WIC (fruits) less frequently, when compared to WIC-participating children in WIC-only households.