2004年,在世界杯(bei)短池賽俄羅(luo)斯站200米混合泳中,劉(liu)子歌獲(huo)得(de)金(jin)牌。同(tong)年,隨(sui)著教練金(jin)煒轉(zhuan)會到上海(hai),成為上海(hai)寶(bao)山體育局寶(bao)山游泳學(xue)校的一名學(xue)生。?
2005年(nian),劉子歌進(jin)入上(shang)海游泳隊(dui)。?
2007年,進入中國國家隊。
2008年(nian)4月,在全國游泳冠軍(jun)賽(sai)暨奧運會選(xuan)拔(ba)賽(sai)中(zhong)獲得(de)女(nv)子200米蝶泳冠軍(jun),并(bing)取得(de)北(bei)京(jing)奧運會參(can)賽(sai)資(zi)格;8月14日,劉子歌在北(bei)京(jing)奧運會女(nv)子200蝶泳比賽(sai)中(zhong),以2分(fen)04秒18獲得(de)金牌,并(bing)打破(po)了世界紀錄。
2009年(nian)4月(yue)(yue),在(zai)(zai)全(quan)國游泳(yong)(yong)(yong)(yong)冠軍賽(sai)(sai)200米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)獲(huo)得(de)銀(yin)牌(pai)(pai),7月(yue)(yue),在(zai)(zai)羅(luo)馬世錦賽(sai)(sai)獲(huo)得(de)200蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)亞(ya)(ya)軍,10月(yue)(yue),在(zai)(zai)十(shi)一(yi)運(yun)會上,以56秒07獲(huo)得(de)100米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)冠軍,并(bing)打(da)破亞(ya)(ya)洲紀(ji)錄(lu)(lu);以2分(fen)(fen)(fen)01秒81獲(huo)得(de)200米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)冠軍,超過了澳(ao)大(da)利亞(ya)(ya)選手斯(si)(si)奇(qi)普保(bao)持(chi)的(de)2分(fen)(fen)(fen)03秒41的(de)世界(jie)紀(ji)錄(lu)(lu);還與隊友合(he)作獲(huo)得(de)女子4×100米(mi)(mi)(mi)混合(he)泳(yong)(yong)(yong)(yong)金(jin)牌(pai)(pai)。11月(yue)(yue),在(zai)(zai)世界(jie)杯短(duan)池游泳(yong)(yong)(yong)(yong)系列賽(sai)(sai)斯(si)(si)德哥爾摩站,以2分(fen)(fen)(fen)02秒50獲(huo)得(de)金(jin)牌(pai)(pai),并(bing)打(da)破了世界(jie)紀(ji)錄(lu)(lu)。在(zai)(zai)國際(ji)泳(yong)(yong)(yong)(yong)聯(lian)短(duan)池游泳(yong)(yong)(yong)(yong)世界(jie)杯賽(sai)(sai)柏林(lin)站,獲(huo)得(de)女子200米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)冠軍,以2分(fen)(fen)(fen)00秒78打(da)破世界(jie)紀(ji)錄(lu)(lu)。同年(nian)12月(yue)(yue),獲(huo)得(de)第五(wu)(wu)屆東亞(ya)(ya)運(yun)動會女子200米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)金(jin)牌(pai)(pai)、亞(ya)(ya)洲游泳(yong)(yong)(yong)(yong)錦標賽(sai)(sai)女子200米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)金(jin)牌(pai)(pai)。2010年(nian)2月(yue)(yue),在(zai)(zai)短(duan)池游泳(yong)(yong)(yong)(yong)世錦賽(sai)(sai)女子200米(mi)(mi)(mi)蝶(die)(die)(die)泳(yong)(yong)(yong)(yong)決賽(sai)(sai)中,劉(liu)子歌開始150米(mi)(mi)(mi)一(yi)路領先,但后(hou)勁不足,最(zui)終(zhong)以2分(fen)(fen)(fen)04秒78僅(jin)列第五(wu)(wu)。在(zai)(zai)女子4×100米(mi)(mi)(mi)混合(he)泳(yong)(yong)(yong)(yong)接力中,與隊友合(he)作獲(huo)得(de)金(jin)牌(pai)(pai)。
2011年(nian)4月(yue),在全(quan)國游泳(yong)(yong)冠軍(jun)(jun)賽,獲得女(nv)(nv)(nv)子(zi)(zi)50米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)第(di)(di)五名(ming)(ming)(ming)、100米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)冠軍(jun)(jun)、200米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)冠軍(jun)(jun)。同年(nian)11月(yue),在短(duan)(duan)池世界(jie)杯北京(jing)站(zhan)女(nv)(nv)(nv)子(zi)(zi)100米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)獲得第(di)(di)四(si)名(ming)(ming)(ming)、女(nv)(nv)(nv)子(zi)(zi)200米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)第(di)(di)四(si)名(ming)(ming)(ming)。同年(nian)8月(yue),在倫敦奧運會女(nv)(nv)(nv)子(zi)(zi)200米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)僅獲得第(di)(di)八名(ming)(ming)(ming)。同年(nian)11月(yue),短(duan)(duan)池游泳(yong)(yong)世界(jie)杯系列賽北京(jing)站(zhan)獲得女(nv)(nv)(nv)子(zi)(zi)100米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)第(di)(di)五名(ming)(ming)(ming)、女(nv)(nv)(nv)子(zi)(zi)200米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)第(di)(di)三名(ming)(ming)(ming);同年(nian)12月(yue),世界(jie)短(duan)(duan)池游泳(yong)(yong)錦標賽獲得女(nv)(nv)(nv)子(zi)(zi)100米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)獲得第(di)(di)二(er)名(ming)(ming)(ming)、女(nv)(nv)(nv)子(zi)(zi)200米(mi)(mi)(mi)蝶(die)(die)泳(yong)(yong)第(di)(di)四(si)名(ming)(ming)(ming)。
2013年,全國游泳(yong)(yong)(yong)冠軍賽女子200米蝶(die)泳(yong)(yong)(yong)獲得(de)第(di)二名;同(tong)年8月(yue),世界游泳(yong)(yong)(yong)錦標賽女子200米蝶(die)泳(yong)(yong)(yong)獲得(de)冠軍。