diff --git a/backend/services/blockchain-service/src/infrastructure/persistence/mappers/deposit-transaction.mapper.ts b/backend/services/blockchain-service/src/infrastructure/persistence/mappers/deposit-transaction.mapper.ts
index dab37f55..3f0a1d35 100644
--- a/backend/services/blockchain-service/src/infrastructure/persistence/mappers/deposit-transaction.mapper.ts
+++ b/backend/services/blockchain-service/src/infrastructure/persistence/mappers/deposit-transaction.mapper.ts
@@ -17,6 +17,11 @@ export class DepositTransactionMapper {
       throw new Error(`DepositTransaction ${prisma.id} missing accountSequence or userId`);
     }
 
+    // 使用 amountFormatted 重建 TokenAmount
+    // amountFormatted 已经是正确的人类可读格式（如 1000000.00000000）
+    // 用 decimals=8 与 toFixed(8) 保持一致，确保 toFixed(8) 返回相同的值
+    const amount = TokenAmount.fromFormatted(prisma.amountFormatted.toString(), 8);
+
     const props: DepositTransactionProps = {
       id: prisma.id,
       chainType: ChainType.create(prisma.chainType),
@@ -24,7 +29,7 @@ export class DepositTransactionMapper {
       fromAddress: EvmAddress.fromUnchecked(prisma.fromAddress),
       toAddress: EvmAddress.fromUnchecked(prisma.toAddress),
       tokenContract: EvmAddress.fromUnchecked(prisma.tokenContract),
-      amount: TokenAmount.fromDecimal(prisma.amount, 18),
+      amount,
       blockNumber: BlockNumber.create(prisma.blockNumber),
       blockTimestamp: prisma.blockTimestamp,
       logIndex: prisma.logIndex,