The abundant production of fly ash from coal based thermal power plants as waste products becoming problem for their disposal and it is also hazardous to the environment. The inclusion of fly ash in concrete reduces the environmental pollution and improves the workability and durability properties of concrete. The present work has been carried out to find rapid chloride penetration test of fly ash and fibre reinforced concrete with different water binder ratios. The polypropylene fibre fraction 0%, 0.15%, 0.25%, 0.30% were used to find out the optimum volume fraction of glass fibres. For each mix standard sizes of cylinder were cast and tested for RCPT at 28 and 90 days. The percentage of fibre increases, the values of charge passed increases upto volume content 0.30%.