Salinity is one of the major constraintsin the rice production worldwide. Rice plants have moderate tolerance towardssalinity. Salinitychangescell membrane permeability and fatty acid compositionsby releasing the free fatty acids. Nonetheless, the effect of exogenous fatty acid such as arachidonic acid (AA) on rice grown on saline soil is yetunknown. Theobjective of the current study isto determine the effectofAA onthe morphological traits and freefatty acidsofrice plantgrown under saline conditions.Rice plants grown on saline soil (EC=12 ds/m)were treated with 50 μMAAon day 45 after transplant. Leaves and panicleswere sampledafter two weeks of treatment and analysed for fatty acid profile using GC-MS. Themorphological traits were observedat the maturity stage. Results showed that AA treatment improved the grain fill-in of the saline stress riceand reduced the accumulation of free fatty acids in the cell. The AAtreatment also increased the linoleic acid (18:2), linolenic acid (18:3) in paniclesand, dihomo-γ-linolenic acid(20:3) and nervonic acid (24:1) in leaves. The finding suggests that exogenous AAregulates salinity stress in rice by reducing the accumulation offree fatty acids.