The field trials were conducted in the farm of El-Gemmeiza Agric. Res. Station, El-Gharbeia Governorate, during winter growing season of 2017/2018. This study aimed to improve physical and chemical properties as induced by the soil conditioners (sulphur(S), phosphogypsum(PG) and liquid calcium carboxylic acid (LCC)) on availability of essential nutrients and their positively effects on  growth onion and this chemical composition. The experiment was designed in a complete randomized blocks design with three replicates. The treatments were (T1) control, (T2) sulphur (S) application at 1.50 ton ha^-1 ,(T3)sulphur (S) application at 2.50 ton ha^-1 ,(T4) phosphogypsum(PG) application at 5.00 ton ha^-1 , (T5) phosphogypsum(PG) application at 10.00 ton ha^-1 ,(T6) liquid calcium carboxylic acid (LCC) application at 5.00 liter ha^-1 and (T7) liquid calcium carboxylic acid (LCC) application at 10.00 liter ha^-1. It was observed that application of S, PG and LCC at the high rate recorded maximum values of total water stable aggregates, hydraulic conductivity and cumulative infiltration. Regardless of application of S, PG and LCC up to 1.50 ton ha^-1, 10 ton ha^-1 and 10 liter ha^-1 level respectively led to decreased the soil properties (soil pH, exchangeable sodium and ESP) and increased the CEC, exchangeable cations , soil available NPK than other treatments. Soil treated with soil amendments showed apparent increases of macronutrients in both bulb and leaves onion, crude protein in bulb, chlorophyll a, chlorophyll b, chlorophyll a+b and carotenoid than control. The study recommends adding soil conditioners improve the physo- chemical properties and onion growth.