Initial critical response to Lenny was positive. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream critics, the album has received an average score of 69, based on 12 reviews, which indicates "generally favorable reviews".
Stephen Thomas Erlewine wrote a positive review for AllMusic, commenting that "There may not be singles that are as immediately grabbing as "It Ain't Over 'til It's Over", "Let Love Rule" and "Are You Gonna Go My Way", but there are no dull spots, either, and this easily stands alongside his first three albums as a set of classy, near-irresistible pop for listeners weaned on classic and college rock, which is a wholly welcome surprise." Blender commented about "its 12 tracks", writing that "they are unusually raucous and raw, as Kravitz finds a comfort zone with turbocharged punk and arena rock." No. 7 US Adult Top 40
- "Stillness of Heart" – No. 18 US Adult Top 40,
- "Believe in Me"
- "If I Could Fall in Love" – No. 40 US Adult Top 40
- Lenny Kravitz – vocals, electric guitar, drums, bass guitar (tracks 1–4, 7–9, 11, 12), acoustic guitar (tracks 3, 4, 7), Mini-Moog (tracks 5, 6, 10), drum programming (tracks 5, 6), stylophone (track 3), piano (track 9), timpani and orchestral cymbals (track 10), string arrangement (tracks 3, 5, 7, 8), orchestral arrangement (tracks 4, 10)
- Craig Ross – electric guitar (tracks 3, 4, 11), Hammond organ (track 3)
- Henry Hirsch – Hammond organ (track 12), string arrangement (tracks 3, 5, 7), orchestral arrangement (track 10)
- David Baron – sequenced synthesizer (track 10), string arrangement (track 7), orchestral arrangement (track 10)
Production and artwork
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!scope="row"|Japanese Albums (Oricon)
|6
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!scope="row"|Spanish Albums (AFYVE)
|align="center"|12
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Year-end charts
{| class="wikitable sortable plainrowheaders" style="text-align:center"
|+2001 year-end chart performance for Lenny
! scope="col"| Chart (2001)
! scope="col"| Position
|-
! scope="row"| Austrian Albums (Ö3 Austria)
| 55
|-
!scope="row"| Canadian Albums (Nielsen SoundScan)
| 136
|-
! scope="row"| Dutch Albums (Album Top 100)
| 96
|-
! scope="row"| Italian Albums (FIMI)
| 39
|-
! scope="row"| Swedish Albums (Sverigetopplistan)
| 88
|}
{| class="wikitable sortable plainrowheaders" style="text-align:center"
|+2002 year-end chart performance for Lenny
! scope="col"| Chart (2002)
! scope="col"| Position
|-
! scope="row"| Austrian Albums (Ö3 Austria)
| 35
|-
!scope="row"|Canadian Alternative Albums (Nielsen SoundScan)
| 79
|-
! scope="row"| German Albums (Offizielle Top 100)
| 17
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! scope="row"| Swiss Albums (Schweizer Hitparade)
| 39
|-
! scope="row"| US Billboard 200
| 179
|}