二者区别在于具体含义的不同。
1、on one's own意为“靠自己的力量、独自地”，在句子中可做状语，独立使用，相当于一个副词。
例句：
①He never joins with us.He always plays on his own.
他从不和我们在一起。他总是自己单独玩。
②He drew the conclusion by building on his own investigation.
他根据自己的调查研究作出结论。
③He's doing it on his own account, not for anyone else.
他干这事是为了自己，而不是为其他任何人。
2、by one's own不可以单独使用，因为其中的own是形容词，后接名词，才可以在句子中充当状语。例如中文“靠某人自己的双手”可以表达为："by one's own hands"。
例句：
①He must not measure his neighbour's corn by his own bushel.
他不应该拿自己的标准去衡量邻居。
②The story goes that he died by his own hands, but this looks rather suspicious.
谣传他已经自杀，但我对此半信半疑。
③My father gained a bare livelihood of family by his own hands.
父亲靠自己的双手勉强维持家计。
扩展资料
近义词：alone
释义：
adj.单独的； 独一无二的； 独自的；
adv.单独地； 独自地； 孤独地； 只，只有
例句：
1、I would have to learn, little by little, to exist alone.
我得慢慢学会独自生活。
2、The doll-like figures in these stories are unlike anybody, let alone oneself.
这些故事中的玩偶形象跟谁都不像，更不用说像自己了。