One of the innovations needed to create lightweight wall is possible by using Styrofoam as a partially fine aggregate substitution. This study was conducted to study the flexural strength of Styrofoam lightweight concrete panel walls with a high-volume fly ash content in a square column connection. Methodology: The size of the wall panel used is 120 x 30 x 10 cm with 10 x 10 cm square column holes as support on both sides. In the centre of the wall panel, four square holes with a dimension of 18 x 4 cm were created. The variations of fine aggregate replacement with Styrofoam were 50% and 60% by the volume of fine aggregate, while the use of Fly ash is 50% as partially cement substitution. SCC (Self Compacting Concrete) method was used to manufacture this kind of concrete. Results: The results of Slump Flow T50 test for 50% and 60% Styrofoam variations are 64 cm and 59 cm, while the concrete weight-volumes are1387.7 kg/m 3 and 1259.4 kg/m 3. Compressive strength test for both variations are 42.62 Kg/cm 2 and 31.71 kg/cm 2. Stiffness values for both variations are 1434.7 N/mm and 1125 N/mm. This study also analysed the maximum length of the panel wall in which for 50% Styrofoam variation is 4 m and 60% Styrofoam variation is 3.2 m. Applications/ Originality/ Value: Research on Styrofoam concrete hollow panel walls incorporated with high volume fly ash is significant since it opens the possibility to reduce the Styrofoam waste.