Food insecurity, linked to poor diet quality and diversity, heightens vulnerability to malnutrition, particularly in fishing households due to poverty, income seasonality, and environmental shifts. This study investigates food security, dietary diversity, and nutritional status of children (36 to 59 months) from fishing households in San Pablo City, Laguna, Philippines. Purposive sampling yielded eighty-six (86) households with a 100% participation rate. Food security and dietary diversity were assessed using Household Food Insecurity Access Scale (HFIAS) and Food Consumption Score (FCS) while the nutritional status of the children was derived from the Oplan Timbang Plus (OPT+) data in March 2023. Mean, frequency, percentage calculations, and Kendall’s rank correlation test (α=0.05) were used for data analysis. Results indicated that majority of the household heads earn less than Php 10,000 (44.2%) and spend less than Php 7,000 (75.6%) on food every month. Only (5.8%) were food-secure while the rest were food insecure, classified as moderate (45.3%), mild (39.5%), and severe (9.3%). Most households have acceptable food consumption (70.9%) with a mean FCS of 55.6 ± 20.6. Stunting (45.3%), underweight (36.1%), and wasting (19.8%) were observed among the preschool children. Kendall’s rank tau tests demonstrated a positive moderate correlation between household food security status and dietary diversity (CI:95%, p=0.0040, τ=0.2902) and monthly income (CI:95%, p=0.0141, τ=0.2332). Stunting and underweight were also strongly and moderately correlated to household food insecurity (CI:95%, p=2.11e-05, τ=0.4152; CI:95%, p=0.0027, τ=0.2969) and poor dietary diversity (CI:95%, p=0.0474, τ=0.2004). The persistence of food insecurity and malnutrition necessitates effective interventions and policies targeting children and vulnerable groups in fishing communities.