Abstract: At present, Shamir secret sharing algorithm is a classic cloud data privacy protection technology, but this technology still has some shortcomings. It cannot resist the collusion attack of CSP. Using this algorithm will cause large storage overhead. As the amount of data increases, it will also bring users greater computing overhead. To solve these problems, a new cloud data hiding scheme is proposed. FMSR coding was used to block the data, initially hiding the data while reducing the size of data blocks involved in subsequent calculations, thereby reducing storage and computing costs. LFSR algorithm was used to generate pseudo-random numbers, and the real secret was converted into a false secret to resist collusion attacks. Iterative polynomial was used to hide pseudo secret blocks. Through theoretical and security analysis, the scheme can reduce storage overhead and resist CSP collusion attacks. Through experimental analysis, the proposed scheme can reduce user computing overhead.