Aims:  To determine the status of oestrogen receptor (ER) subtypes (ERα and ERβ) in lobular carcinoma in situ (LCIS) of the breast.Methods and results:  Forty‐seven cases of LCIS and six cases with normal breast lobules were subjected to immunohistochemistry and evaluated for ERα, ERβ and progesterone receptor (PR) expression. mRNA for ERα, ERβ1 and ERβ2 were quantified in LCIS and normal lobules using laser microdissection coupled with real‐time polymerase chain reaction. LCIS showed a higher level of steroid receptor protein expression than normal lobules. There was no difference in ERβ1 gene or ERβ protein expression between normal lobules, pure LCIS, or LCIS associated with invasive breast cancer. No significant difference in expression of either ERα or ERβ was found between pure LCIS and LCIS associated with invasive cancer. However, PR was significantly lower in those cases of LCIS with associated invasive than in those without synchronous invasive disease.Conclusions:  Increased expression of steroid receptors in LCIS suggests their possible role in the biology of LCIS and, for PR, could influence the predisposition of women diagnosed with LCIS to develop invasive breast carcinoma.